2007: I think Hpakan will remain the same for the next 500 + years.
(via Gemological Digest, Vol.2, No.4, 1989) Bertil Lintner writes:
Abstract
There are few areas in the world which offer as much fascination to the gemologist as Upper Burma. Throughout history this region has been off limits to outsiders. This situation was merely perpetuated with the coming-to-power of the xenophobic Ne Win regime in 1962. Since that time eyewitness accounts have been few and far between. This is indeed unfortunate, for Upper Burma contains two of the planet’s premier gem deposits: ruby/sapphire mines at Mogok and the world’s only jadeite deposits of consequence near Mogaung.
The following article is based on the author’s lengthy journey through Burma’s Kachin State. He gives a fascinating account of the jade trade, describing the often romantic political and legal complexities surrounding the marketing and distribution of the gem known to Chinese as “the stone of heaven.”
There may not be many places in Southeast Asia where people are prepared to pay US$100 for a bottle of Hennessy cognac or French champagne, $10 for a pint of beer, $3 for a bowl of noodle soup, and over $130 for a pair of running shoes from South Korea. But exorbitant prices seem to matter little at Hpakan in northern Burma, where some people are said to have become overnight millionaires by accidentally unearthing a big green boulder while digging latrines outside their houses.
Described as a mini “Hong Kong” by many visitors, Hpakan, the “jade capital” of Burma’s Kachin State, is reputed to have a much wider and even more exclusive variety of contraband goods than the famous night market in Mandalay. Perfumes from Paris, American cigarettes, tinned New Zealand butter, Australian cheddar and German pressure cookers—anything and everything is available at freewheeling Hpakan.
Thousands of fortune seekers flock to the jade mines every year, ranging from affluent Chinese laopans, or bosses, from Mandalay, Rangoon, Bangkok and Hong Kong, to teenagers and people in their early twenties, all with dreams of striking it rich.
“It’s a very special atmosphere there. The gambling fever affects everyone and people live in perpetual presence,” said one young Kachin student who had spent his summer holiday searching for jade at Hpakan:
“Anything goes. Young boys and girls meet and build huts in the forest, where they stay and dig together. Even married people seem to forget their marital ties as soon as they have crossed the Uru Hka river.”
The jade diggers usually fall into two categories. They are either seasonal migrants—farmers, workers, students, and government employees—or full-time professionals.
Officially, the Burmese government allows jade mining only at three places: Hpakan itself, and at the neighboring villages of Waje Maw and Sanchyoi. There, the work is carried out by government-employed diggers who receive a monthly salary plus a 10-20% commission on any high quality jade they manage to find. That jade is later sold to international buyers at the annual government-organized extravaganza at the Inya Lake Hotel in Rangoon.
But, given the vast amounts of money in circulation, it is hardly surprising that the laopans, and even private diggers, can bribe the local officials who are more than eager to get their share of Hpakan’s fortunes. It is even said that big Hong Kong-based jade companies have their own, secret representatives at Hpakan to supervise the work, organize the buying, and hire agents for transporting the boulders out from the mining areas.
Local people with experience in jade mining told this correspondent that Burmese Army officers go looking for ‘illegal diggers—and even shoot them if they cannot pay the demanded fees:
“If the people killed have only a small amount, the officers keep it for themselves. But if they have a lot of jade, it’s difficult to hide and so the army people have to hand it over to the government. That jade also ends up at the Inya Lake Hotel,” charged one source from Hpakan.
Corruption in Burma—a country which virtually lives off smuggling and black market trade—is by no means confined to Hpakan, but the situation there is aggravated by the immense wealth of the place, and the fact that some major jade syndicates are reputed to be connected with drug smuggling rings. Several big traders are said to bring jade out of Hpakan—and local hard currencies, such as opium and heroin, in to finance the purchase of jade at the mines.
Like most other towns in Kachin State, Hpakan is supplied by convoys of lorries (F.E.E.R, 28 May 1987) which move with tight security because of fear of ambushes which are frequently launched by the rebel Kachin Independence Army (KIA). These convoys carry daily necessities, arms and ammunition for the Burmese Army, and, for a fee, various kinds of contraband, according to Hpakan souces.
The rampant graft and corruption at Hpakan could be the reason why army units are deployed there on a rotational basis. One battalion of government troops never stays more than six months in the area—enough time for an officer to make a fortune, but not too long to let rivalry erupt between him and his colleagues, who are waiting for their turn of duty at the jade mines.
However, disputes between army officers reportedly do occur every now and then. The most serious clash in recent years erupted between some officers from the Myitkyina-based 29th battalion, which was stationed at Hpakan for six months during 1985, and the then commander of the northern command of the Burmese Army, Brig Gen Lazum Kam Hpang. The latter, a Kachin himself, had severely reprimanded the officers from the 29th battalion for alleged maltreatment of Kachin civilians in the jade mines area, even threatening to punish them. It all ended in a shoot out at a coffee shop in Myitkyina on November 16, 1985; Brig Gen Lazum Kam Hpang was fatally wounded and died in the hospital shortly afterwards.
At first, the local authorities put the blame on the Kachin rebels in the KIA, but when no substantial evidence could be presented to support that allegation, the whole story was quickly hushed up, and it went unreported in the government controlled Burmese media. Army deployment in the jade mining region is heavy, but nevertheless confined to Hpakan town, and the government controlled jade mines of Waje Maw and Sanchyoi. In addition, a company size contingent is always based at the Lung Hkang junction, where the road to Hpakan branches off to Kamaing in the Hukawng Valley. The surrounding hills and the countryside—where most jade mines are located—including the famous mines at Tawmaw north of Hpakan, have long been controlled by the KIA.
The Kachin rebels first occupied parts of the jade mine area in 1963, and tax on the trade as well as yearly licenses, or so-called digging tickets have since been a main source of income for the KIA. The rebel army maintains a number of checkpoints around the mines—including one on the main Lung Hkang Kamaing motor road—where a 10-30% tax is levied on the jade which merchants bring out from the area.
A Kachin rebel taxation office told this correspondent that yearly takings, including tickets at the KIA toll gates around Hpakan amount to Kyats 8-10 million—but he added that only 25% of the jade may pass through the rebel checkpoints:
“The most precious pieces are smuggled out, and the total value of the jade extracted from the Hpakan area could be as much as Kyats 100 million a year,” the officer said.
The real profit, however, is made when the jade reaches the Thai border, usually the first destination outside Burma on the long smuggling route from Burma’s Kachin State to Hong Kong, the world’s main marketing center for jade. Prices at the Thai border are said to be five to ten times as high as in Hpakan, and sometimes even more if the jade is of unusually good quality. But before the jade comes that far it has to pass through many stages, involving more bribes to government officials, and additional tax to other rebel groups along the way through Burma to Thailand.
The clandestine representatives of the international jade syndicate at Hpakan—who are not in a position to evade bribes, but who seldom pay tax to the KIA—are reported to bring most of their cut and uncut jade boulders down the Uru Hka river, in a westerly direction towards Homalin on the Chindwin river. In this way, they bypass the KIA’s checkpoints on the Kamaing road and south of Hpakan.
Usually, blocks of jade are tied to rafts or small country boats for the downriver journey to Homalin. There is only one Burmese Army outpost along this route—at Nawngpu-awng—and bribes ease the way here as well as in Hpakan. From Homalin, the jade continues by steamer down the Chindwin, or hidden in paddy baskets and under heaps of straw on bullock carts, until it reaches the railhead of Monywa. From there, rail and lorries take over for the onward trip to Mandalay, Taunggyi, and even as far south as Rangoon and Moulmein, depending on the final destination of the cargo.
Along the way to Monywa, a small percentage of the jade is diverted to India via the Tamu-Moreh border market in the Manipur State. This border crossing point is a main center for the contraband trade between Burma and India, but the demand for jade is not high among the Indians; the customers on that side are the 40000 or so ethnic Chinese who live in Calcutta, and a few other places in eastern and northeastern India.
An elaborate network of local agents, who usually have connections among themselves even if they work for different syndicates, are said to be responsible for the various stages along the routes. One group may take care of the Hpakan-Mandalay section, another would be in charge of the stretch from Mandalay to Taunggyi, Rangoon or Moulmein, and a third party would ensure that the goods are delivered across the border in Thailand, or sometimes by boat from Moulmein to Penang in Malaysia, or even on to Singapore.
During the last leg of the journey, before reaching the Thai border, some traders have to pay transit fees to the various insurgent groups there—the Karen rebel army if the goods are going south to Bangkok, the Karenni army if the destination is Mae Hong Son and Chiang Mai via Loikaw in Kayah State.
But these minor routes would be used by smaller traders only; most of the border between Thailand and Burma’s Shan State is controlled either by remnants of the Nationalist Chinese Koumintang, or by Chang Shee-fu (alias Khun Sa) and his powerful private army. Both groups are dominated by ethnic Chinese businessmen who run their own jade syndicates—and mercenary armies across the border with Burma.
The jade trade, which has brought a fair amount of the present wealth and well being to Chiang Mai, is seen by some observers as potentially even more lucrative than the closely connected drug trade, which sometimes is carried out by the same syndicates. That is becoming more important now when international police agencies in Thailand are stepping up their drives against narcotics smugglers. Unlike heroin, jade becomes a legal commodity once it has crossed the international frontier.
Running the gauntlet into Thailand is becoming tougher, and while most heroin refineries still appear to be located near the Thai-Burmese border, increased police supervision in Thailand is seen by many observers as the reason why more and more drugs now make a U-turn near the frontier, back into Burma and along new ones through that country.
New smuggling routes exist along which both jade and heroin pass through central Burma—where international police control is none existent—down to the Tenasserim coast. Well informed sources assert that it is not difficult to bring any kind of goods through Burma—if one can afford to pay the price.
Small traders reportedly deposit their goods with the policemen who check the passenger baggage on the Myitkyina-Mandalay and Mandalay-Rangoon trains; it is also possible to leave the contraband with the train driver, these sources say.
The fee here would not be more than a few thousand Kyats, or less than 10% of value of the goods, which can be heroin, raw opium or jade. Bigger traders, though, need more sophisticated solutions to the problem. By bribing government officials, they can obtain letters of introduction stating that they are intelligence agents on duty, and that their luggage, therefore, should not be checked. People issuing these letters range from local army officers to government ministers, the sources say, and the fee depends on the authority of the official in question and the solvency of the individual trader. Other certificates can be more cryptic, stating that the bearer should not be recruited as a porter to carry arms and ammunition for government troops—a common practice whenever the Burmese Army launches operations against country’s many insurgent groups—which indirectly means that he is an important person. Bearers of such certificates have assured this correspondent that their vehicles are never searched by the police or the army.
But now it seems that recent events along the Sino-Kachin border may change all this and drastically alter the entire network of underground trade through Burma down to Thailand, and to Malaysia and Singapore. As a result of the rapid modernization drive launched by Deng Xiaoping in China, baggy trousers and old Mao jackets are losing their former popularity—and jade is back again. According to one source along the Sino-Kachin border:
“Previously, the only decoration Chinese women could wear were red Mao badges. Now, also the Chinese in mainland China want to set off the beauty of their women as the overseas Chinese do. Jade is undergoing a renaissance in the People’s Republic.”
Buyers from Peking and Shanghai recently have come down to the border between China and Burma’s Kachin State, and they are reported to be gradually improving their knowledge, almost matching the Chinese jade merchants of pre-revolutionary days. Most of this jade seems to be earmarked for the domestic market, while some gemstones, jewelry and carvings are sold in Hong Kong via the many emporia the Chinese government maintains in the still-British territory.
The exact amount of jade now being sent to China is difficult to determine, and as far as the value goes, it may not exceed five percent of the total output at Hpakan. But it is increasing steadily, since it is a much easier route than down to Thailand.
This correspondent saw convoys of jade-laden elephants and mules winding their way up the steep mountain passes along the Sino-Kachin frontier, and there was little doubt that the routes of the former jade caravans to Tengchong in Yunnan Province were open again. The most frequently used routes lead from Hpakan to the KIA-controlled border settlements of Hkala Yang, Pa Jau and Loije. A smaller amount reaches China via Kambaiti Pass to the north, which is controlled by the Burmese Communist Party (BCP). All three aforementioned gates are in Kachin State—but most jade goes from the center at Mandalay via Lashio to Juili north of the Shweli border river in order to avoid the rebel tax gates.
The difficulty in bringing profitable goods other than jade to China could explain why many traders still prefer the much longer and more risky journey down to Thailand. One source also pointed out that the traders do not want to work only; they also want amusement:
“In Thailand, there are massage parlors and nightclubs; in China there is nothing like that yet. It’s more fun to spend your money in Chiang Mai than in Juili or Tengchong.”
But even when taking this into consideration, it is nevertheless not far-fetched to assume that the direct routes to China are destined to become more important, especially when Hong Kong returns to Chinese hands in 1997. Whether that will severely affect the jade trade with Thailand remains to be seen, but, without doubt, that route will inevitably lose much of its present significance. If that should prove to be the case, the drug syndicates which are based along the Thai-Burmese border may also be affected. Without jade as a supplementary, and complementary, commodity, the heroin trade will become less profitable and more difficult to continue effectively, some observers suggest.
“Jade is popular in China now. But neither the Chinese authorities, nor the Kachin rebels who tax the trade, would allow heroin to come along with it. The Chinese welcome green jade, but not the white powder.”
Gemologists distinguish two types of jade: jadeite and nephrite. The origin of the word jade is believed to be the expression piedra de ijada of the Spanish Conquistadores, which means stone of the side or flank. Wearing jade next to one’s kidney or liver was believed to provide healing benefits. Similarly, nephros is the Greek word for kidney, and this led to the term nephrite.
One difference between these two species is that jadeite is a vitreous and shiny stone, while nephrite has a more oily or waxy finish. Nephrite is also called green stone in New Zealand, where the native Maoris carved it for fish hooks, knives, needles and war clubs—and for religious objects, or tikis, which were worn for decoration and spiritual protection.
The Aztecs and Mayans of Central America revered the beauty of both jadeite and nephrite, and vast quantities were taken away by the Conquistadores when they occupied these ancient empires. Fair quality jadeite has been found in Guatemala, but the location of the original Mayan Mines still remains a mystery. Small quantities of jadeite have also been found in the USSR, Japan, and in California in the US.
But, it is the Kachin Hills of northern Burma which for centuries have been the world’s only supplier of top quality jadeite. The discovery that fine green jadeite occurred in the Kachin Hills is said to have been made accidentally by a Yannanese petty trader in the 13th century. The story runs that when about to return home from a trading trip to northern Burma, he picked up a stone to balance the load of his mule. It proved to be jade of excellent quality, and subsequently a large party returned to procure more. These merchants were unsuccessful, however, as no local people were able to tell them where this kind of stone could be found.
Several more missions came from China, but they were equally unsuccessful. The keenness of the Chinese to locate the jade deposits was not difficult to understand; nephrite jade had been known and appreciated in China from early times in history. And to the Chinese, jade was not just another stone—protective qualities were also attributed to it. Many Chinese children, even today, wear a kind of jade padlock around their necks to protect them from diseases. One type of Chinese nephrite is known as mutton fat, having a yellowish white color. Another variety is called chicken bone and it has a slightly lighter hue. Nephrite most commonly occurs in a green color. But even the finest nephrite is no match for the emerald green jadeite which the Yunnanese trader had brought back from the Kachin Hills.
The final discovery of the jade mines came after 1784, when centuries of hostilities between the traditional enemies, Burma and China, were terminated. Adventurous traders from Yunnan once again entered the Kachin Hills in search of the green stones. This time they managed to find them; big, precious boulders along the banks of the Uru Hka river, near the village of Hpakan, northwest of Mogaung. From the end of the 18th century onwards, the jade trade with Yunnan expanded rapidly. The only hindrances were rough roads and a climate in which malaria flourished. A Chinese temple at Amarapura near Mandalay in northern Burma has a long list of the names of more than 6000 traders who perished while searching for jade in the Kachin Hills—and the roll-call includes only the names of well known traders for whom funeral rites were held. The actual total would be many times that number, had all the small traders and adventurers been included.
The original rulers of the jade mine area were the Shan sawbwas of Mogaung—a place—a name which is actually a Burmese corruption of the Shan Mong Kawng. But pressed between the politically more powerful Burmans to the south—and the warlike Kachins, who pushed down from the north, the sawbwas of Mogaung lost their independence soon after the trade with China had been established.
The state was subjugated by the Burmese Kings of Ava in 1796, and the mines came within the domains of a number of Kachin chiefs, or duwas. The most powerful of these was the Kansi duwas, who drew considerable royalties on the jade trade—apart from the revenue collected by the Burmese governor in Mogaung. The Burmese Kings quickly became aware of the importance of the jade trade; already by 1806 a Burmese Collectorate with an armed force was located in Mogaung.
Although there is no jade at Mogaung itself, the town soon became the headquarters of the jade trade in Burma. Few merchants themselves actually went up to the mines. Instead, they hired local people to dig for them, and the jade brought down to Mogaung where it was bought by the Chinese and taxed by the Burmese authorities. From Mogaung, caravans—often protected by Panthay, or Muslim Chinese, mercenaries from Yunnan—wound their way over the high mountain passes east of the Irrawaddy, across the frontier into China. The demand for jadeite was universal throughout China, and the Hpakan mines were the only source of this superior type and quality.
The trade with China has since been interrupted only four times. The first cut-off occurred during the First Opium War between Britain and China in the 1840’s, when Cantonese traders no longer could come to buy the stones at Kunming in Yunnan. When the war was over, the trade commenced again, but it soon came to a new halt when the Panthay Muslims rebelled in 1857. The unrest in Yunnan, which prevailed for many years, prompted some traders to negotiate with the Burmese Kings, and a new route was opened by sea from Canton, up the Irrawaddy to Mandalay.
From then on the trade picked up and, before long, the mountain routes via Yunnan came into use once more. It continued uninterrupted until World War Two and the Japanese invasions of China and Burma in the 1940s. The fourth time the trade was stopped was, naturally, after the communist revolution in China in 1949. This brought the trade with China to a standstill, which at first appeared to be permanent. Hong Kong then emerged as the world’s leader center, with Chiang Mai in northern Thailand as the most important nexus along the long and dangerous route from Hpakan. By then, the mines had been nationalized by the Burmese government following the military takeover in 1962—at least in theory.
The jade-belt roughly stretches from Hweka north of Indawgyi Lake to Singkaling Hkamti on the Chindwin river, with the main mining area suited between Hpakan and Tawmaw near the Uru Kha river. Jade is also found at a few other places in Kachin State, notably at Mandawng and Shangaw east of the Nmai Hka river—but the quality there is said to be inferior to that of Hkapan-Tawmaw area.
A trained eye is said to be able to distinguish one type of jade from another, and even say from which mine the stone has been brought. But not until it has been cut. Through millions of years of exposure to weathering, jade boulders oxidize, developing a gray to brown exterior skin. Such a skin is largely opaque, hiding the color and quality of the material underneath. Thus no one is able to say exactly what the quality of a piece is until this skin is removed by grinding, or the boulder opened by sawing. It may be the highly prized, translucent emerald green known in the trade as imperial jade, sometimes worth thousands of dollars per carat, or it could be of an opaque white color worth practically nothing. Part of the excitement surrounding the jade business is exactly this: buying the unskinned rough is very much of a gamble. Traders can make a big profit if lucky, or lose their shirts if the quality is low.
This gambling connected with the purchase of rough jadeite could be one of several reasons why jade became so popular with the Chinese—and why the communists later frowned upon it after the 1949 revolution. Now, when China is rediscovering many of its former traditions, the traders from Peking and Shanghai appear to have settled for a compromise: jade, minus the gamble.
“They want to cut the stones before they buy them,” said one local jade expert on the Sino-Kachin border.
Hong Kong is usually the final destination of most jadeite which comes out from Burma via Thailand. The British colony entered the international jade market when the Japanese occupied the former trading centers of Peking, Shanghai and Canton during World War Two—and when the communists took over China in 1949. These events forced two waves of jade merchants to flee to Hong Kong, which soon became the world’s main marketplace for cut jade. Today, either they or their descendants are among the most prominent of the 40 members of the Hong Kong Jade & Stone Manufacturer’s Association.
Despite being carried out by people in business suits and neckties, Hong Kong’s jade auctions are still steeped in ancient Chinese ritual. Whereas a Western auctioneer is all noise and movement, his Cantonese counterpart will stand still and wait for customers to come up to him and offer their bids, using the legendary finger sign bidding technique. The prospective buyer will privately touch the fingers of the auctioneer under a piece of cloth, and just whisper if he is indicating hundreds or thousands of Hong Kong dollars. Keeping all the secret bids in his head, the auctioneer will finally clasp the fingers of the bidder who has offered the most suitable price.
A jade deal has been made.
Sunday, May 13, 2007
Friday, May 11, 2007
Asian Markets Push Illegal Ivory
BBC News writes:
The illegal ivory trade is expanding, driven by East Asian crime syndicates, according to the wildlife trade monitoring network Traffic.
The syndicates gather ivory in Africa for export to East Asian countries. The biggest market is mainland China, though there is also significant trade to other countries such as Thailand and the Philippines, and to Hong Kong.
Traffic says there are 92 illegal ivory seizures per month, and the number of large hauls has doubled in a decade. Its report will be presented to next month's meeting of the Convention on International Trade in Endangered Species (Cites), where wildlife campaigners hope it will put pressure on governments whose countries are used by the traffickers.
"The relevant question is whether Cites is going to crack down or not, whether governments are going to show some political will," said Sue Lieberman, director of the global species programme at WWF which runs Traffic together with the World Conservation Union (IUCN).
"The Asian market is the key. It is thriving again in Thailand, and a lot of Chinese businesses have moved into Africa, for example timber companies, which means more ivory is coming out," she told the BBC News website.
Big hauls up
Traffic bases its report on an analysis of nearly 12,400 records of ivory seizures in 82 countries dating back to 1989 as part of the Elephant Trade Information System (Etis). It clearly identifies the Democratic Republic of Congo, Cameroon and Nigeria as the main sources of illegal ivory.
"With myriad conflicts, central Africa is currently haemorrhaging ivory," observed Tom Milliken, director of Traffic's Africa programme. "These three countries are major conduits for trafficking illegal ivory from the region to international markets, particularly in Asia."
The number of seizures fell between 1990 and 1995, but there has been a rising trend since then. The number of large hauls - above one tonne - has also risen, which Dr Lieberman believes "demonstrates greater sophistication, organisation and finance".
China is identified as the single biggest market, though Traffic says enforcement has improved markedly in the last five years. On the African side, the conservation group singles out Ethiopia for praise as a country which has effectively implemented an action plan drawn up by Cites four years ago, clamping down on its domestic ivory market.
More info @ http://news.bbc.co.uk/2/hi/science/nature/6644365.stm
The illegal ivory trade is expanding, driven by East Asian crime syndicates, according to the wildlife trade monitoring network Traffic.
The syndicates gather ivory in Africa for export to East Asian countries. The biggest market is mainland China, though there is also significant trade to other countries such as Thailand and the Philippines, and to Hong Kong.
Traffic says there are 92 illegal ivory seizures per month, and the number of large hauls has doubled in a decade. Its report will be presented to next month's meeting of the Convention on International Trade in Endangered Species (Cites), where wildlife campaigners hope it will put pressure on governments whose countries are used by the traffickers.
"The relevant question is whether Cites is going to crack down or not, whether governments are going to show some political will," said Sue Lieberman, director of the global species programme at WWF which runs Traffic together with the World Conservation Union (IUCN).
"The Asian market is the key. It is thriving again in Thailand, and a lot of Chinese businesses have moved into Africa, for example timber companies, which means more ivory is coming out," she told the BBC News website.
Big hauls up
Traffic bases its report on an analysis of nearly 12,400 records of ivory seizures in 82 countries dating back to 1989 as part of the Elephant Trade Information System (Etis). It clearly identifies the Democratic Republic of Congo, Cameroon and Nigeria as the main sources of illegal ivory.
"With myriad conflicts, central Africa is currently haemorrhaging ivory," observed Tom Milliken, director of Traffic's Africa programme. "These three countries are major conduits for trafficking illegal ivory from the region to international markets, particularly in Asia."
The number of seizures fell between 1990 and 1995, but there has been a rising trend since then. The number of large hauls - above one tonne - has also risen, which Dr Lieberman believes "demonstrates greater sophistication, organisation and finance".
China is identified as the single biggest market, though Traffic says enforcement has improved markedly in the last five years. On the African side, the conservation group singles out Ethiopia for praise as a country which has effectively implemented an action plan drawn up by Cites four years ago, clamping down on its domestic ivory market.
More info @ http://news.bbc.co.uk/2/hi/science/nature/6644365.stm
On Distribution Channel
Gabi Tolkowsky writes:
Once you have a new cut you must be able to distribute and market it. You have to combine efforts with someone who is interested. You must also consider is the price interesting, is the cut beautiful enough to show others, can you make a continuous supply? You have to have a regular supply of rough to continue to provide a distributor with enough diamonds to supply the public. You must think about whether the cut will be successful enough to take a share of the market and you must be able to move away from it, if people get tired of it. You must also consider your market. Are you targeting the upscale or mass market? Are the cuts for small or large stones? From my personal side, I am still surprised by the lack of knowledge about the diamonds themselves. The industry has invented cuts that are fascinating and beautiful, but we don’t market them because we are not sure there is a demand for it.
Once you have a new cut you must be able to distribute and market it. You have to combine efforts with someone who is interested. You must also consider is the price interesting, is the cut beautiful enough to show others, can you make a continuous supply? You have to have a regular supply of rough to continue to provide a distributor with enough diamonds to supply the public. You must think about whether the cut will be successful enough to take a share of the market and you must be able to move away from it, if people get tired of it. You must also consider your market. Are you targeting the upscale or mass market? Are the cuts for small or large stones? From my personal side, I am still surprised by the lack of knowledge about the diamonds themselves. The industry has invented cuts that are fascinating and beautiful, but we don’t market them because we are not sure there is a demand for it.
On Marketing Magic
Gabi Tolkowsky writes:
During the 1960s marketing diamonds changed. It opened up the market for owning diamonds to everyone. People began to buy diamonds because they could. Millions of individuals started buying diamonds. Each person had an individual sense of beauty, and each one wanted to have something individual. The industry started to design more jewelry, much of which had diamonds with the same style of cut. Consumers became more sophisticated and they wanted something unique for themselves. Then cutters began to study more—how could they make diamonds have more light, more brilliance? This is how you start to invent new cut. As a cutter you see the transformation of the rough to polished. You see what is firey and if you are creative, you can invent a new cut.
During the 1960s marketing diamonds changed. It opened up the market for owning diamonds to everyone. People began to buy diamonds because they could. Millions of individuals started buying diamonds. Each person had an individual sense of beauty, and each one wanted to have something individual. The industry started to design more jewelry, much of which had diamonds with the same style of cut. Consumers became more sophisticated and they wanted something unique for themselves. Then cutters began to study more—how could they make diamonds have more light, more brilliance? This is how you start to invent new cut. As a cutter you see the transformation of the rough to polished. You see what is firey and if you are creative, you can invent a new cut.
The Valuations/Assessments/Appraisals Minefield
(via Gemological Digest, Vol.2, No.4, 1989) Bernice Backler writes:
Introduction
Very regrettably, over the years many so-called valuations emanating from around the world have proven to be nothing but worthless bits of paper, due to the fact they have been performed by persons holding an I.B.A (Incompetent Bumbling Amateur) Diploma. These valuations are incomprehensible, inaccurate, incomplete and inadmissible in court, all due to incompetent ignoramuses trying to do something they know not one iota about.
This brings to mind a photograph in a recent jewelry magazine showing Joe Soap, expert jeweler, assessing a valuable gem. Joe Soap was shown standing in a ridiculous position, his ample stomach pushed out, holding a something up to the heavens and viewing it through a jeweler’s glass, with the glass held the wrong way around. Or was he seeking divine inspiration?
As gemologists with reasonable international standing, we (my firm) decided some years ago that we would specialize in valuations, doing them the way they should be done, as distinct from the expensive thumbsucks (of which we have a very large file). One such example of a thumbsuck appraisal was given as follows: “ two round diamonds in a gold band”—this from a self-styled manufacturer/faceter who has never manufactured anything or ever cut a stone in his life.
The client who wishes to know what his jewelry is worth, for whatever reason, puts his trust—his entire trust—in the jeweler, and pays good money for what he thinks is a proper valuation, only to discover later that the appraisal is not worth the paper it is written on. Should not the client be entitled to a fair, honest and thorough valuation? Remember, it is the mug who sits on the other side of the counter who pays our salaries.
I will attempt to set out hereunder exactly what the client should get for his/her money in the way of proper valuation/appraisal/assessment.
What is a valuation?
A valuation report is first and foremost a legal document which sets out in full detail all the important points of the piece of jewelry concerned.
Creation of this document must be carried out with the scrupulous degree of care required by law. The art and science of valuation shows the jeweler/gemologist/appraiser at the highest pitch of his faculties; all his knowledge is summoned and focused on the subject in question. His appreciation of what is beautiful, his eye for fine color in gems, his experience of what the market regards as highly valued and sought after—all of these skills are critically exercised.
A true expert is obliged to reach his decision impartially and scientifically, to substantiate it and issue it written (usually typed) form. The issuing of an accommodating valuation (where the client required the actual value to be altered to suit his/her requirements) is contrary to moral principles (in fact, fraud could possibly be proved), as is also the issuing of an irresponsible or careless valuation.
Why do you need a valuation?
There are two main forms of valuation:
1. Insurance: which gives details of full replacement value on basis of like for like according to the values current at the time.
2. Probate: this is a valuation for death duty purposes where the valuation is based purely on materials, i.e. weight of gold and/or value of gems without taking into account workmanship, or applicable taxes or mark ups.
There is, very regrettably, one more form of valuation peculiar to the jewelry trade and it causes considerable damage to honest reputations and generates much bad feeling. This is brought about by a client who goes to a professional appraiser first, and then (usually) goes to a retailer for reassurance that the valuation is correct.
Unfortunately there are unscrupulous persons in every country who will deliberately undervalue goods, either to discredit the competition or because they wish to buy the article (s) in question. This practice is called poising among the jewelry trade, for obvious reasons.
What is a valuator/appraiser?
The appraiser must be a member/graduate of a recognized gemological and/or appraisal body, such as the Gemological Association of Great Britain (GAGB), the Gemological Institute of America (GIA), or any other foreign association or institute. By so being he constantly receives updated information on the gem and jewelry scene, like new techniques, new stones, new fakes (of which roughly one a month rears its ugly head). He must also keep himself informed by getting magazines, trade publications, etc. from as many sources as possible and, importantly, keep his price lists up to date.
An appraiser must reveal openly and fairly al he knows about the stone in question—after all, his primary responsibility is to the person to whom he is giving the valuation. It goes without saying that if he is a member of gemological and/or appraisal association, he will understand the need to have all the relevant instrumentation to help him sort out the various stones and fakes, such a microscope, refractometer, polariscope, spectroscope, photometer (or colorimeter), high intensity (fiber optic) lamp, konoscope, diamond grading light box, and all the other instruments, etc. ad nauseam.
In plain English, he has to keep his nose to the grindstone to keep up to date in this rapidly changing world. If he does not, he is forever lost. I know of one so-called gemologist who proudly states that after he got his piece of paper 19 years ago, he has not since opened a book because I know it all. This gentleman’s knowledge was not worth the ink on his diploma six months after he got it. To have a piece of paper hanging on the wall does not qualify one to be an appraiser; a professional appraiser is constantly studying and thus is qualified by continuing experience. In a nutshell, an appraiser never finishes training because he is always learning new concepts, ideas, etc.
What an appraiser needs to know
Obviously, the first prerequisite is a sound fundamental knowledge of gemology, backed up by a good library for reference purposes. The second item is a diamond price index. A very good service is provided by a New York firm (Rapaport) who issues a weekly sheet giving not only current diamond wholesale prices covering the entire color and clarity range in sizes from 0.01 to 5.00 carats, but also other relevant market information. The service is considered by some to be rather pricey, but to the professional appraiser it is worth every penny.
Colored stone prices—ruby, sapphire, emerald, opal, and other lesser gems—can be obtained also from sources in the States. Again the subscription price is not exactly cheap at first glance, but represents a wise (and essential investment) for the professional appraiser.
So much for the obvious. As nearly all prices used internationally are given in US dollars, the appraiser has to be able to work his currency in relation to the dollar; diamonds all have base prices quoted in dollars at a wholesale level. He also must take into account inflation rates, import taxes, surtaxes, excise duties, sales taxes, labor costs, and know the various mark-ups from manufacturers to retailers. Additionally, he must also follow the daily fluctuations of precious metal prices and keep a register of these fluctuations, as well as have knowledge of metal testing and assaying so that he can accurately describe the gold/silver/platinum content of a piece. Of major importance is the ability to fully describe the piece in terms that will satisfy both other appraiser/gemologists to whom the report might be shown, while at the same time being understandable to the layperson/customer for whom the report is prepared. Detailed worksheets should be used to jot down the appraiser’s findings and these must be kept on file for reference in later years. The appraiser must also be prepared to stand up in court and support his valuations to everyone’s satisfaction, especially the courts’. This is one place where the keeping of accurate records pays off.
In doing any appraisal, the appraiser must always remember that, next to one’s house, one’s jewelry is probably the biggest investment that a person will ever make. If you were ill and needed a doctor you would not go to a plumber, but strangely, people are always prepared to go to any Tom, Dick or Harry who says he is an appraiser and end up with a worthless piece of paper which states two round diamonds in a gold ring.
Length of training
1. Professional appraiser: Usually two to three years, either in-house or home study, and then constant updating of this knowledge for the rest of one’s life (which, incidentally, costs quite a whack of money).
2. Retail jeweler: Usually three to four days (based on worldwide examples) and then many consider themselves fully trained, often never taking any more courses or doing very little further updating. But, because they are called jewelers they think they have a god-given right to do valuations, and this is where the majority of our thumbsucks come into the picture.
Cost of training
1. Professional: Over the years many tens of thousands of dollars when one takes into account the cost (ever increasing) of instrumentation, books, magazines, fees to professional bodies, fees to institutions, updated price lists and all of the many other items which go into making his job top of the line.
2. Retailer: A three to four days course on jewelry appraisal which costs between $200-500 today, from various teaching establishments.
Ethics of the jeweler/appraiser
When a person goes to a jeweler/appraiser, he goes because he has confidence in that person. This confidence is the jeweler/appraiser’s most precious possessions and a very high ethical standard must be maintained in a profession where the client is at such a disadvantage (through ignorance of the nature, properties and value of gems and metals). This ethical code involves truth in all directions, especially in the description of the goods. It is a responsibility which cannot and must not be taken lightly.
Disclosure of treatments
There is a moral and legal obligation on the part of the appraiser/gemologist/jeweler to disclose to his client the fact that his stone has been treated (and so is no longer totally natural), if, in fact, such is the case. Some of the most common treatments we see today are:
a. Oiled emeralds, to enhance color and clarity.
b. Glass-filled (surface repaired) rubies, to fill in surface pits and cavities.
c. Laser-drilled diamonds, to burn out clarity defects.
d. Dyed gems, such as lapis and turquoise, to enhance color, or plastic impregnation.
e. Heat treatment of ruby, sapphire, aquamarine, tanzanite, etc. to enhance color and/or clarity.
f. Irradiation of blue topaz, to enhance color.
This list could go on forever because there are so many different treatments used today to improve the appearance and salability of gemstones. Gems & Gemology, the official organ of the Gemological Institute of America, as well as other gemological journals, contains details of the various treatments in use today. The gemologist’s bible on the subject of gem treatments is Gemstone Enhancement by Dr Kurt Nassau. Any appraiser worthy of his salt should be able to detect treatments quite easily.
Loss to client and insurance company due to poor appraisals
Let us assume that you have a poor valuation on a ring and the value is given as, say, $1000. The insurance company charges, say, 4% to cover your ring, so you pay them $40. You lose your ring and then it is discovered that to replace like with like would cost you $10000, and the insurance company’s premium would have been $400. You, the client, carry the onus, so you would be under insured. The insurance company brings in their average clause and you get $100. Not a very pretty picture, is it? Maybe the insurance company will not even offer you $100; they may just cut the claim entirely.
How a physical valuation should be performed
The ideal way is to perform the valuation in front of the client where he can see each step as it is being done. Not only does this impress him with the amount of work which goes into a valuation, but it also does away with the oft-seen charge that he changed my stone, which could be difficult to prove or disprove if the appraisal were done in a back office, away from the customer.
It must be borne in mind that some rings and other pieces of jewelry are brought in such a dirty condition that after cleaning, the piece may appear totally different compared to the lifeless object that it once was.
Legal position of the professional appraiser/retail jeweler
First we will discuss the oft-heard phrase he changed my stone. If this charge cannot be proved and the person so charged has been brought into disrepute by false claim, he can then sue the person who made the claim, and could perhaps take them to the cleaners.
Stones do get changed by unscrupulous traders from time to time—remember we are dealing with one of the world’s costliest items—and the only way to sort this out is to have a full and factual appraisal, where the parameters of one can be checked against the other.
Both the appraiser and the retail jeweler can be legally sued for the same things—these are normally fraud, misrepresentation, incompetence, negligence, etc. where appraisals are concerned.
An example of how an appraisal should be done
Recently, a diamond dealer I know sold a diamond at a little above the current wholesale price to a friend of his to have made up into an engagement ring. The cost of the stone was $1800, it weighed 0.63ct.was of H color (top commercial white), and of SI (slightly included) clarity. The ring, and a wedding band with three small diamonds therein, was subsequently made up by a manufacturing jeweler (not my firm) and was then taken to a so-called expert retail jeweler for appraisal. His appraisal took ten minutes, covered three lines, was handwritten (apparently no copy was kept) on a cardboard certificate and stated:
“Round brilliant diamond, 0.53ct, color H, P2 (second pique) plus 3 x .03 side stones in gold wedding set.”
He the offered to buy the diamond for $1200. In his thumbsuck appraisal he lost ten points on the diamond’s weight, gave it a second pique (which is one step away from reject) and a worthless description. His offer to buy the diamond smacked of misrepresentation in that he saw he could get a reasonably good diamond for virtually nothing. To say that the client was no impressed would be putting it mildly.
The dealer immediately telephoned us to say that he would bring his client out, and we did an appraisal as it should have been done.
John Doe
1. One yellow gold solitaire engagement ring stamped 18 karat, weighing 4.35 g, set with one modern round brilliant cut, SI clarity, top commercial white (H color) diamond estimated to weigh approx. 0.64ct, measuring 5.41mm, of good polish with pointed culet, and unpolished light to medium girdle, very slight fluorescence, Okuda angle 80%+ (very good); and one modern round brilliant cut, SI clarity, weak commercial white (J color) diamond in each bow-tie shaped shoulder, estimated to weigh approx. 0.03ct each, measuring approx. 2mm each, of medium polish with pointed culet, unpolished girdle, and non-fluorescent. All claws new and in good condition. Identifying marks: 18 karat. All clarities determined at 10x. Diamond colors photometrically confirmed.
Appraised value = $4150.00
2. One yellow gold ladies’ matching wedding ring stamped 18 karat, weighing 2.8g, set with one SI clarity (at 10x), weak commercial white (J color) diamond, estimated to weight approx. 0.03 ct, measuring approx. 2mm, of medium polish with pointed culet, and non-fluorescent. Identifying marks: 18 karat. All claws new and in good condition.
Appraised value = $313.00
Shank widths:
Engagement ring: 4mm – 2 mm
Wedding ring: 4mm
Shank thicknesses:
Engagement ring: 1mm
Wedding ring: 1mm
Accolade
I recently appraised some jewelry for a lady going to Great Britain. Regrettably, she lost our valuation certificate, did not realize we kept copies of all appraisals done, and had her jewelry revalued in England. On her return she stopped in and we saw the British appraisal. After making allowances for the two different taxing systems, we discovered we were within £1 of the British appraisal. If one can’t call that spot on, I do not know what is.
Conclusion
In conclusion, let me aim a barbed dart at the people who load the market with thumbsuck valuations, guesstimates, and whatever other names apply. These people are mainly retailers. Let me say the following: “Know your limitations. Do not try to do everything. Succeed at what you can do, and do it very well indeed.”
We are all in the game to make money and it does not matter whether we make money selling jewelry products, or in the case of appraiser, selling knowledge. What does matter is that we do it with integrity.
In all fairness, it must be stated that there are certain retail jewelers who, because of their limitations, refuse point blank to do appraisals.
Introduction
Very regrettably, over the years many so-called valuations emanating from around the world have proven to be nothing but worthless bits of paper, due to the fact they have been performed by persons holding an I.B.A (Incompetent Bumbling Amateur) Diploma. These valuations are incomprehensible, inaccurate, incomplete and inadmissible in court, all due to incompetent ignoramuses trying to do something they know not one iota about.
This brings to mind a photograph in a recent jewelry magazine showing Joe Soap, expert jeweler, assessing a valuable gem. Joe Soap was shown standing in a ridiculous position, his ample stomach pushed out, holding a something up to the heavens and viewing it through a jeweler’s glass, with the glass held the wrong way around. Or was he seeking divine inspiration?
As gemologists with reasonable international standing, we (my firm) decided some years ago that we would specialize in valuations, doing them the way they should be done, as distinct from the expensive thumbsucks (of which we have a very large file). One such example of a thumbsuck appraisal was given as follows: “ two round diamonds in a gold band”—this from a self-styled manufacturer/faceter who has never manufactured anything or ever cut a stone in his life.
The client who wishes to know what his jewelry is worth, for whatever reason, puts his trust—his entire trust—in the jeweler, and pays good money for what he thinks is a proper valuation, only to discover later that the appraisal is not worth the paper it is written on. Should not the client be entitled to a fair, honest and thorough valuation? Remember, it is the mug who sits on the other side of the counter who pays our salaries.
I will attempt to set out hereunder exactly what the client should get for his/her money in the way of proper valuation/appraisal/assessment.
What is a valuation?
A valuation report is first and foremost a legal document which sets out in full detail all the important points of the piece of jewelry concerned.
Creation of this document must be carried out with the scrupulous degree of care required by law. The art and science of valuation shows the jeweler/gemologist/appraiser at the highest pitch of his faculties; all his knowledge is summoned and focused on the subject in question. His appreciation of what is beautiful, his eye for fine color in gems, his experience of what the market regards as highly valued and sought after—all of these skills are critically exercised.
A true expert is obliged to reach his decision impartially and scientifically, to substantiate it and issue it written (usually typed) form. The issuing of an accommodating valuation (where the client required the actual value to be altered to suit his/her requirements) is contrary to moral principles (in fact, fraud could possibly be proved), as is also the issuing of an irresponsible or careless valuation.
Why do you need a valuation?
There are two main forms of valuation:
1. Insurance: which gives details of full replacement value on basis of like for like according to the values current at the time.
2. Probate: this is a valuation for death duty purposes where the valuation is based purely on materials, i.e. weight of gold and/or value of gems without taking into account workmanship, or applicable taxes or mark ups.
There is, very regrettably, one more form of valuation peculiar to the jewelry trade and it causes considerable damage to honest reputations and generates much bad feeling. This is brought about by a client who goes to a professional appraiser first, and then (usually) goes to a retailer for reassurance that the valuation is correct.
Unfortunately there are unscrupulous persons in every country who will deliberately undervalue goods, either to discredit the competition or because they wish to buy the article (s) in question. This practice is called poising among the jewelry trade, for obvious reasons.
What is a valuator/appraiser?
The appraiser must be a member/graduate of a recognized gemological and/or appraisal body, such as the Gemological Association of Great Britain (GAGB), the Gemological Institute of America (GIA), or any other foreign association or institute. By so being he constantly receives updated information on the gem and jewelry scene, like new techniques, new stones, new fakes (of which roughly one a month rears its ugly head). He must also keep himself informed by getting magazines, trade publications, etc. from as many sources as possible and, importantly, keep his price lists up to date.
An appraiser must reveal openly and fairly al he knows about the stone in question—after all, his primary responsibility is to the person to whom he is giving the valuation. It goes without saying that if he is a member of gemological and/or appraisal association, he will understand the need to have all the relevant instrumentation to help him sort out the various stones and fakes, such a microscope, refractometer, polariscope, spectroscope, photometer (or colorimeter), high intensity (fiber optic) lamp, konoscope, diamond grading light box, and all the other instruments, etc. ad nauseam.
In plain English, he has to keep his nose to the grindstone to keep up to date in this rapidly changing world. If he does not, he is forever lost. I know of one so-called gemologist who proudly states that after he got his piece of paper 19 years ago, he has not since opened a book because I know it all. This gentleman’s knowledge was not worth the ink on his diploma six months after he got it. To have a piece of paper hanging on the wall does not qualify one to be an appraiser; a professional appraiser is constantly studying and thus is qualified by continuing experience. In a nutshell, an appraiser never finishes training because he is always learning new concepts, ideas, etc.
What an appraiser needs to know
Obviously, the first prerequisite is a sound fundamental knowledge of gemology, backed up by a good library for reference purposes. The second item is a diamond price index. A very good service is provided by a New York firm (Rapaport) who issues a weekly sheet giving not only current diamond wholesale prices covering the entire color and clarity range in sizes from 0.01 to 5.00 carats, but also other relevant market information. The service is considered by some to be rather pricey, but to the professional appraiser it is worth every penny.
Colored stone prices—ruby, sapphire, emerald, opal, and other lesser gems—can be obtained also from sources in the States. Again the subscription price is not exactly cheap at first glance, but represents a wise (and essential investment) for the professional appraiser.
So much for the obvious. As nearly all prices used internationally are given in US dollars, the appraiser has to be able to work his currency in relation to the dollar; diamonds all have base prices quoted in dollars at a wholesale level. He also must take into account inflation rates, import taxes, surtaxes, excise duties, sales taxes, labor costs, and know the various mark-ups from manufacturers to retailers. Additionally, he must also follow the daily fluctuations of precious metal prices and keep a register of these fluctuations, as well as have knowledge of metal testing and assaying so that he can accurately describe the gold/silver/platinum content of a piece. Of major importance is the ability to fully describe the piece in terms that will satisfy both other appraiser/gemologists to whom the report might be shown, while at the same time being understandable to the layperson/customer for whom the report is prepared. Detailed worksheets should be used to jot down the appraiser’s findings and these must be kept on file for reference in later years. The appraiser must also be prepared to stand up in court and support his valuations to everyone’s satisfaction, especially the courts’. This is one place where the keeping of accurate records pays off.
In doing any appraisal, the appraiser must always remember that, next to one’s house, one’s jewelry is probably the biggest investment that a person will ever make. If you were ill and needed a doctor you would not go to a plumber, but strangely, people are always prepared to go to any Tom, Dick or Harry who says he is an appraiser and end up with a worthless piece of paper which states two round diamonds in a gold ring.
Length of training
1. Professional appraiser: Usually two to three years, either in-house or home study, and then constant updating of this knowledge for the rest of one’s life (which, incidentally, costs quite a whack of money).
2. Retail jeweler: Usually three to four days (based on worldwide examples) and then many consider themselves fully trained, often never taking any more courses or doing very little further updating. But, because they are called jewelers they think they have a god-given right to do valuations, and this is where the majority of our thumbsucks come into the picture.
Cost of training
1. Professional: Over the years many tens of thousands of dollars when one takes into account the cost (ever increasing) of instrumentation, books, magazines, fees to professional bodies, fees to institutions, updated price lists and all of the many other items which go into making his job top of the line.
2. Retailer: A three to four days course on jewelry appraisal which costs between $200-500 today, from various teaching establishments.
Ethics of the jeweler/appraiser
When a person goes to a jeweler/appraiser, he goes because he has confidence in that person. This confidence is the jeweler/appraiser’s most precious possessions and a very high ethical standard must be maintained in a profession where the client is at such a disadvantage (through ignorance of the nature, properties and value of gems and metals). This ethical code involves truth in all directions, especially in the description of the goods. It is a responsibility which cannot and must not be taken lightly.
Disclosure of treatments
There is a moral and legal obligation on the part of the appraiser/gemologist/jeweler to disclose to his client the fact that his stone has been treated (and so is no longer totally natural), if, in fact, such is the case. Some of the most common treatments we see today are:
a. Oiled emeralds, to enhance color and clarity.
b. Glass-filled (surface repaired) rubies, to fill in surface pits and cavities.
c. Laser-drilled diamonds, to burn out clarity defects.
d. Dyed gems, such as lapis and turquoise, to enhance color, or plastic impregnation.
e. Heat treatment of ruby, sapphire, aquamarine, tanzanite, etc. to enhance color and/or clarity.
f. Irradiation of blue topaz, to enhance color.
This list could go on forever because there are so many different treatments used today to improve the appearance and salability of gemstones. Gems & Gemology, the official organ of the Gemological Institute of America, as well as other gemological journals, contains details of the various treatments in use today. The gemologist’s bible on the subject of gem treatments is Gemstone Enhancement by Dr Kurt Nassau. Any appraiser worthy of his salt should be able to detect treatments quite easily.
Loss to client and insurance company due to poor appraisals
Let us assume that you have a poor valuation on a ring and the value is given as, say, $1000. The insurance company charges, say, 4% to cover your ring, so you pay them $40. You lose your ring and then it is discovered that to replace like with like would cost you $10000, and the insurance company’s premium would have been $400. You, the client, carry the onus, so you would be under insured. The insurance company brings in their average clause and you get $100. Not a very pretty picture, is it? Maybe the insurance company will not even offer you $100; they may just cut the claim entirely.
How a physical valuation should be performed
The ideal way is to perform the valuation in front of the client where he can see each step as it is being done. Not only does this impress him with the amount of work which goes into a valuation, but it also does away with the oft-seen charge that he changed my stone, which could be difficult to prove or disprove if the appraisal were done in a back office, away from the customer.
It must be borne in mind that some rings and other pieces of jewelry are brought in such a dirty condition that after cleaning, the piece may appear totally different compared to the lifeless object that it once was.
Legal position of the professional appraiser/retail jeweler
First we will discuss the oft-heard phrase he changed my stone. If this charge cannot be proved and the person so charged has been brought into disrepute by false claim, he can then sue the person who made the claim, and could perhaps take them to the cleaners.
Stones do get changed by unscrupulous traders from time to time—remember we are dealing with one of the world’s costliest items—and the only way to sort this out is to have a full and factual appraisal, where the parameters of one can be checked against the other.
Both the appraiser and the retail jeweler can be legally sued for the same things—these are normally fraud, misrepresentation, incompetence, negligence, etc. where appraisals are concerned.
An example of how an appraisal should be done
Recently, a diamond dealer I know sold a diamond at a little above the current wholesale price to a friend of his to have made up into an engagement ring. The cost of the stone was $1800, it weighed 0.63ct.was of H color (top commercial white), and of SI (slightly included) clarity. The ring, and a wedding band with three small diamonds therein, was subsequently made up by a manufacturing jeweler (not my firm) and was then taken to a so-called expert retail jeweler for appraisal. His appraisal took ten minutes, covered three lines, was handwritten (apparently no copy was kept) on a cardboard certificate and stated:
“Round brilliant diamond, 0.53ct, color H, P2 (second pique) plus 3 x .03 side stones in gold wedding set.”
He the offered to buy the diamond for $1200. In his thumbsuck appraisal he lost ten points on the diamond’s weight, gave it a second pique (which is one step away from reject) and a worthless description. His offer to buy the diamond smacked of misrepresentation in that he saw he could get a reasonably good diamond for virtually nothing. To say that the client was no impressed would be putting it mildly.
The dealer immediately telephoned us to say that he would bring his client out, and we did an appraisal as it should have been done.
John Doe
1. One yellow gold solitaire engagement ring stamped 18 karat, weighing 4.35 g, set with one modern round brilliant cut, SI clarity, top commercial white (H color) diamond estimated to weigh approx. 0.64ct, measuring 5.41mm, of good polish with pointed culet, and unpolished light to medium girdle, very slight fluorescence, Okuda angle 80%+ (very good); and one modern round brilliant cut, SI clarity, weak commercial white (J color) diamond in each bow-tie shaped shoulder, estimated to weigh approx. 0.03ct each, measuring approx. 2mm each, of medium polish with pointed culet, unpolished girdle, and non-fluorescent. All claws new and in good condition. Identifying marks: 18 karat. All clarities determined at 10x. Diamond colors photometrically confirmed.
Appraised value = $4150.00
2. One yellow gold ladies’ matching wedding ring stamped 18 karat, weighing 2.8g, set with one SI clarity (at 10x), weak commercial white (J color) diamond, estimated to weight approx. 0.03 ct, measuring approx. 2mm, of medium polish with pointed culet, and non-fluorescent. Identifying marks: 18 karat. All claws new and in good condition.
Appraised value = $313.00
Shank widths:
Engagement ring: 4mm – 2 mm
Wedding ring: 4mm
Shank thicknesses:
Engagement ring: 1mm
Wedding ring: 1mm
Accolade
I recently appraised some jewelry for a lady going to Great Britain. Regrettably, she lost our valuation certificate, did not realize we kept copies of all appraisals done, and had her jewelry revalued in England. On her return she stopped in and we saw the British appraisal. After making allowances for the two different taxing systems, we discovered we were within £1 of the British appraisal. If one can’t call that spot on, I do not know what is.
Conclusion
In conclusion, let me aim a barbed dart at the people who load the market with thumbsuck valuations, guesstimates, and whatever other names apply. These people are mainly retailers. Let me say the following: “Know your limitations. Do not try to do everything. Succeed at what you can do, and do it very well indeed.”
We are all in the game to make money and it does not matter whether we make money selling jewelry products, or in the case of appraiser, selling knowledge. What does matter is that we do it with integrity.
In all fairness, it must be stated that there are certain retail jewelers who, because of their limitations, refuse point blank to do appraisals.
The Muppet Movie
Memorable quote (s) from the movie:
Kermit (Jim Henson): Life is like a movie. Write your own ending. Keep believing. Keep pretending. We've done just what we've set out to do. Someday you'll find it, the rainbow connection. The lovers, the dreamers, and you!
Kermit (Jim Henson): Life is like a movie. Write your own ending. Keep believing. Keep pretending. We've done just what we've set out to do. Someday you'll find it, the rainbow connection. The lovers, the dreamers, and you!
Reliability Of Origin Determination For Gemstones
(via Gemological Digest, Vol.3, No.1, 1990) Dr Henry A Hanni writes:
Definition: Origin = geographical place where a gemstone is situated.
This is either the primary deposit in the parent rock or a secondary deposit where the gemstones have been accumulated after decomposition of the parent rock. Since the term Burma, Pailin and Kashmir have a geographical meaning, they should not be used to express a gemstone color type, because it is common knowledge that a particular deposit may produce different shades of colors, some of which may be found in other deposits, as well.
The need for certification of a gemstone’s origin seems to be limited to only a few species or varieties of gems, and to a small group of quite famous deposits. In certain cases, a cut stone can express its place of origin through its physical and chemical properties and by its inclusions and growth structure, as long as these are clearly distinguishable from all other types. Thus these properties must be unique, either alone or in combination. The greater the number of individual and characteristic properties found in a particular stone, the more reliable is the determination of origin. Valuable characteristics should not only positively testify to a certain origin, but the same time excludes other origin possibilities.
Because of the above, experts involved in origin determination must be aware not only of the properties and characteristics of gems from famous sources, but of the properties and characteristics of all other similar sources. Only the exclusive features, those which are unique to a particular deposit can be called diagnostic properties.
Depending on the complexity of the formation of the gem crystals and on the geologic environment, the type and number of characteristics can be quite varied. Formation of gems requires some indispensable main conditions without which the gem cannot grow, as well as side conditions which can influence the growth but are not essential to the growth. Some of these main and minor conditions which can influence the properties and characteristics of gems include:
- availability of the main constituent chemical elements, and the growth speed.
- the types of available trace elements, and their concentrations.
- transport processes and the transport media involved.
- the type of energy source involved in formation (intrusive pegmatite, metamorphic, etc.)
- pressure from free oxygen.
- cooling rate after formation.
- deformation history of the parent rock and the growing crystal.
- protogenetic inclusions, reflecting the parent rock.
- syngenetic inclusions, reflecting the transport medium and genetic formation type.
All of these factors can influence the individual characteristics of a gemstone crystal, resulting in differences in:
- the size and shape of crystals, and their growth zoning.
- color, color homogeneity, color variations.
- trace element mixture (including invisible trace elements).
- solid inclusions and twinning.
- the state of healed fissures (i.e. fingerprints), geometry and degree of restoration.
- nature of fillings in negative crystal voids.
- composition of fluid inclusions.
What sort of diagnostic origin information can we collect from a cut gemstone?
Characteristic features:
- Microscopic investigation
Color and growth zoning relative to the crystallographic structure, color inhomogeneity, twinning type (s), internal strain, observation of type and distribution of solid and fluid/gas inclusions, type of healing fissures.
- Physical and optical properties
Specific gravity, refractive indices, double refraction (birefringence), fluorescent behavior, absorption spectroscopy (UV, VIS, IR), spin resonance spectroscopy, composition of fluids and minimum temperature/pressure estimation (heat/freezing stage microscope).
- Chemical determination
Trace element determination by energy dispersive x-ray fluorescence analysis (EDS-XFA), amount or relative ratio of trace elements present (e.g. Ti, Fe, Cr, V, Ga, etc.), chemical analysis of inclusions by electron beam instruments (scanning electron microscope, electron microprobe).
Some of the observed and collected characteristics are not restricted to a certain deposit, but in combination may be of diagnostic value. Those observations which are unique for a special deposit are the most important diagnostic features in regard to origin determination. Successful origin determination involves the following steps:
Observation → Comparison → Interpretation
↑ ↑ ↑
Scrutiny Comprehension Prudence
How can we get reliable basic knowledge about materials of definite known origin?
The most simple answer to this question is to collect samples directly at the mine or source. In many cases, though, this is not possible, since the source may be exhausted, or located in an inaccessible location. Therefore we must collect our reference material from a safe source, like a museum, an old collection, etc. Information on gemstone sources can also be obtained from books and publications. Many historical gemstone sources are discussed in reference books. Geographical maps give specific information on the type of deposit, scientific publications reveal the properties of the respective material, chemical analyses of the gemstones and their inclusions are published. All observations must be in agreement with the known facts, e.g. trace elements with spectroscopic analyses, inclusions with geology, etc.
From all this information we gain a very complex view of a gemstone deposit and its production. The more material we investigate, the more dense our network becomes. We are even able to add new observations to the earlier information, building upon it. Sharing and discussing new information with knowledgeable colleagues in the same field provides an added check to our results. But it is still important to revise and recheck the fundamentals of the science by basic research and study of the literature for information on new sources and new techniques. Stagnation is dangerous.
Limitations in the determination of origin
As I have pointed out at the beginning, we use differences in properties as a means of discrimination. Properties which are repeated in stones from more than one source are not valued as diagnostic characteristics, but can nevertheless be helpful in excluding other localities which do not possess these properties. As an example, a certain shade of blue does not prove a certain origin, nor does a misty turbidity. But the misty turbidity in combination with the absence of rutile needles points towards a group of possible origins and excludes some other possibilities of sapphire origins. Within the group of possible origins we may come to a definite source, as long as the stone itself contains enough further evidence pointing towards its origin. It may, for example, exhibit a distinctive absorption curve or spectrum never seen in stones from other localities. At the same time it may show included crystals (identified by an electron beam instrument, which are found only that specific source. These inclusions would, therefore, exclude all other source possibilities.
Origin determination done by the SSEF are not dependent upon a single characteristics only, but are based on at least three independent diagnostic features. Our possibilities are restricted if:
- the properties found in an individual stone may also be found in stones from several localities.
- the stone is found to be free from diagnostic features.
- the possible tests which can be performed is reduced, as, for example, in mounted stones.
- the knowledge base on the type of stone being tested is not broad enough.
Sometimes gemstone deposits and mining areas cross geographic borders, such as the corundum deposits in Kenya/Tanzania and Thailand/Cambodia. In many cases, a producing country may contain different deposits which also vary from one another in the characteristics of the stones produced, such as the corundum deposits in Sri Lanka and Montana (USA).
Many persons in the gem trade have far too little knowledge of the actual range of material coming from particular sources. Even within a single mine, the stones can vary in size, color, transparency and therefore, quality, considerably. This fact must be kept in mind when associating a certain stone with a particular group. It is certainly not the overall appearance visible to the naked eye or with a hand lens which decides the origin of a stone. A possible origin is, on the contrary, proved only by a most careful investigation of all the properties and characteristics carried out by an experienced gemologist using modern scientific equipment. And if there is any doubt or ambiguity, an independent and serious scientist would not issue the report. I would appreciate it very much if the current and future customers of SSEF would understand and accept this policy, especially in cases where our result does not conform with your expectations. In some cases we cannot issue a certificate of origin; in others it turns out differently than what you expected.
I hope to have illustrated by this contribution the possibilities, techniques and the philosophy which governs our work at SSEF, regarding both colored gem reports and, as a supplement, the indications of origin.
We are currently using two different types of phrases when we issue an origin report at SSEF. If the stone shows commonly known and widely accepted diagnostic features, leading us to be very certain of the origin, we make the following statement on the report:
According to your request for an indication of origin, we confirm that the ruby described in the gemstone report mentioned above, shows inclusions as well as physical and chemical properties which, based on present gemological knowledge, are characteristic of a ruby from Burma.
In cases where the stone contains, among commonly accepted characteristic features, those recently observed and certified in our laboratory but not yet published, we use the following expression:
According to your request for an indication of origin, we confirm that the sapphire described in the gemstone report mentioned above, shows inclusions as well as physical and chemical properties, which, in our opinion, are characteristic of a sapphire from Kashmir.
I add to this letter a couple of document copies related with origin determination from SSEF. These contain all cases, including treated stones. I hope they are useful for your work. But again I want to stress that it is the trade who wants us to do these origin determinations. Personally I would prefer to omit origin designations, since they do not prove a certain quality or color of a stone. On the other hand, the buyer should be responsible for what he is spending his money on. He should take care by himself and provide his own basic knowledge, not depending only on the merchant’s or seller’s opinion.
Definition: Origin = geographical place where a gemstone is situated.
This is either the primary deposit in the parent rock or a secondary deposit where the gemstones have been accumulated after decomposition of the parent rock. Since the term Burma, Pailin and Kashmir have a geographical meaning, they should not be used to express a gemstone color type, because it is common knowledge that a particular deposit may produce different shades of colors, some of which may be found in other deposits, as well.
The need for certification of a gemstone’s origin seems to be limited to only a few species or varieties of gems, and to a small group of quite famous deposits. In certain cases, a cut stone can express its place of origin through its physical and chemical properties and by its inclusions and growth structure, as long as these are clearly distinguishable from all other types. Thus these properties must be unique, either alone or in combination. The greater the number of individual and characteristic properties found in a particular stone, the more reliable is the determination of origin. Valuable characteristics should not only positively testify to a certain origin, but the same time excludes other origin possibilities.
Because of the above, experts involved in origin determination must be aware not only of the properties and characteristics of gems from famous sources, but of the properties and characteristics of all other similar sources. Only the exclusive features, those which are unique to a particular deposit can be called diagnostic properties.
Depending on the complexity of the formation of the gem crystals and on the geologic environment, the type and number of characteristics can be quite varied. Formation of gems requires some indispensable main conditions without which the gem cannot grow, as well as side conditions which can influence the growth but are not essential to the growth. Some of these main and minor conditions which can influence the properties and characteristics of gems include:
- availability of the main constituent chemical elements, and the growth speed.
- the types of available trace elements, and their concentrations.
- transport processes and the transport media involved.
- the type of energy source involved in formation (intrusive pegmatite, metamorphic, etc.)
- pressure from free oxygen.
- cooling rate after formation.
- deformation history of the parent rock and the growing crystal.
- protogenetic inclusions, reflecting the parent rock.
- syngenetic inclusions, reflecting the transport medium and genetic formation type.
All of these factors can influence the individual characteristics of a gemstone crystal, resulting in differences in:
- the size and shape of crystals, and their growth zoning.
- color, color homogeneity, color variations.
- trace element mixture (including invisible trace elements).
- solid inclusions and twinning.
- the state of healed fissures (i.e. fingerprints), geometry and degree of restoration.
- nature of fillings in negative crystal voids.
- composition of fluid inclusions.
What sort of diagnostic origin information can we collect from a cut gemstone?
Characteristic features:
- Microscopic investigation
Color and growth zoning relative to the crystallographic structure, color inhomogeneity, twinning type (s), internal strain, observation of type and distribution of solid and fluid/gas inclusions, type of healing fissures.
- Physical and optical properties
Specific gravity, refractive indices, double refraction (birefringence), fluorescent behavior, absorption spectroscopy (UV, VIS, IR), spin resonance spectroscopy, composition of fluids and minimum temperature/pressure estimation (heat/freezing stage microscope).
- Chemical determination
Trace element determination by energy dispersive x-ray fluorescence analysis (EDS-XFA), amount or relative ratio of trace elements present (e.g. Ti, Fe, Cr, V, Ga, etc.), chemical analysis of inclusions by electron beam instruments (scanning electron microscope, electron microprobe).
Some of the observed and collected characteristics are not restricted to a certain deposit, but in combination may be of diagnostic value. Those observations which are unique for a special deposit are the most important diagnostic features in regard to origin determination. Successful origin determination involves the following steps:
Observation → Comparison → Interpretation
↑ ↑ ↑
Scrutiny Comprehension Prudence
How can we get reliable basic knowledge about materials of definite known origin?
The most simple answer to this question is to collect samples directly at the mine or source. In many cases, though, this is not possible, since the source may be exhausted, or located in an inaccessible location. Therefore we must collect our reference material from a safe source, like a museum, an old collection, etc. Information on gemstone sources can also be obtained from books and publications. Many historical gemstone sources are discussed in reference books. Geographical maps give specific information on the type of deposit, scientific publications reveal the properties of the respective material, chemical analyses of the gemstones and their inclusions are published. All observations must be in agreement with the known facts, e.g. trace elements with spectroscopic analyses, inclusions with geology, etc.
From all this information we gain a very complex view of a gemstone deposit and its production. The more material we investigate, the more dense our network becomes. We are even able to add new observations to the earlier information, building upon it. Sharing and discussing new information with knowledgeable colleagues in the same field provides an added check to our results. But it is still important to revise and recheck the fundamentals of the science by basic research and study of the literature for information on new sources and new techniques. Stagnation is dangerous.
Limitations in the determination of origin
As I have pointed out at the beginning, we use differences in properties as a means of discrimination. Properties which are repeated in stones from more than one source are not valued as diagnostic characteristics, but can nevertheless be helpful in excluding other localities which do not possess these properties. As an example, a certain shade of blue does not prove a certain origin, nor does a misty turbidity. But the misty turbidity in combination with the absence of rutile needles points towards a group of possible origins and excludes some other possibilities of sapphire origins. Within the group of possible origins we may come to a definite source, as long as the stone itself contains enough further evidence pointing towards its origin. It may, for example, exhibit a distinctive absorption curve or spectrum never seen in stones from other localities. At the same time it may show included crystals (identified by an electron beam instrument, which are found only that specific source. These inclusions would, therefore, exclude all other source possibilities.
Origin determination done by the SSEF are not dependent upon a single characteristics only, but are based on at least three independent diagnostic features. Our possibilities are restricted if:
- the properties found in an individual stone may also be found in stones from several localities.
- the stone is found to be free from diagnostic features.
- the possible tests which can be performed is reduced, as, for example, in mounted stones.
- the knowledge base on the type of stone being tested is not broad enough.
Sometimes gemstone deposits and mining areas cross geographic borders, such as the corundum deposits in Kenya/Tanzania and Thailand/Cambodia. In many cases, a producing country may contain different deposits which also vary from one another in the characteristics of the stones produced, such as the corundum deposits in Sri Lanka and Montana (USA).
Many persons in the gem trade have far too little knowledge of the actual range of material coming from particular sources. Even within a single mine, the stones can vary in size, color, transparency and therefore, quality, considerably. This fact must be kept in mind when associating a certain stone with a particular group. It is certainly not the overall appearance visible to the naked eye or with a hand lens which decides the origin of a stone. A possible origin is, on the contrary, proved only by a most careful investigation of all the properties and characteristics carried out by an experienced gemologist using modern scientific equipment. And if there is any doubt or ambiguity, an independent and serious scientist would not issue the report. I would appreciate it very much if the current and future customers of SSEF would understand and accept this policy, especially in cases where our result does not conform with your expectations. In some cases we cannot issue a certificate of origin; in others it turns out differently than what you expected.
I hope to have illustrated by this contribution the possibilities, techniques and the philosophy which governs our work at SSEF, regarding both colored gem reports and, as a supplement, the indications of origin.
We are currently using two different types of phrases when we issue an origin report at SSEF. If the stone shows commonly known and widely accepted diagnostic features, leading us to be very certain of the origin, we make the following statement on the report:
According to your request for an indication of origin, we confirm that the ruby described in the gemstone report mentioned above, shows inclusions as well as physical and chemical properties which, based on present gemological knowledge, are characteristic of a ruby from Burma.
In cases where the stone contains, among commonly accepted characteristic features, those recently observed and certified in our laboratory but not yet published, we use the following expression:
According to your request for an indication of origin, we confirm that the sapphire described in the gemstone report mentioned above, shows inclusions as well as physical and chemical properties, which, in our opinion, are characteristic of a sapphire from Kashmir.
I add to this letter a couple of document copies related with origin determination from SSEF. These contain all cases, including treated stones. I hope they are useful for your work. But again I want to stress that it is the trade who wants us to do these origin determinations. Personally I would prefer to omit origin designations, since they do not prove a certain quality or color of a stone. On the other hand, the buyer should be responsible for what he is spending his money on. He should take care by himself and provide his own basic knowledge, not depending only on the merchant’s or seller’s opinion.
Thursday, May 10, 2007
On Feeling Beauty
Gabi Tolkowsky writes:
Why do people buy diamond? Because they are valuable? Perhaps. Because they are so rare? May be tomorrow we will find a big mine. Emotions are very individual. Everybody feels something different. Every diamond is an individual. People who cut diamonds are following the transformation from rough to something beautiful; that’s the challenge. Cutters continue to challenge their knowledge to create beauty. Today you must combine what you do with money considerations. Diamond cutters are tackling an expensive item with the challenge of creating beauty that consumers will want and will buy.
Why do people buy diamond? Because they are valuable? Perhaps. Because they are so rare? May be tomorrow we will find a big mine. Emotions are very individual. Everybody feels something different. Every diamond is an individual. People who cut diamonds are following the transformation from rough to something beautiful; that’s the challenge. Cutters continue to challenge their knowledge to create beauty. Today you must combine what you do with money considerations. Diamond cutters are tackling an expensive item with the challenge of creating beauty that consumers will want and will buy.
On Inventing Cut
Gabi Tolkowsky writes:
Why invent cut? The development of cuts is a young process. It was only at the beginning of the 20th century that the calculations for the best dispersion of light were made. My great uncle did the first calculations and created the modern brilliant cut. He established the parameters, relevant to a round. Rough is not always round. People started to think about following the shape of the rough to get the maximum yield, best dispersion and best light. The brilliant style developed from that and the marquise, oval and pear were cut in that style. Now there are more than 200 shapes of diamonds combined with the different styles of faceting. Why do people go these great lengths? Because we have a fabulous material that refracts light inside.
Why invent cut? The development of cuts is a young process. It was only at the beginning of the 20th century that the calculations for the best dispersion of light were made. My great uncle did the first calculations and created the modern brilliant cut. He established the parameters, relevant to a round. Rough is not always round. People started to think about following the shape of the rough to get the maximum yield, best dispersion and best light. The brilliant style developed from that and the marquise, oval and pear were cut in that style. Now there are more than 200 shapes of diamonds combined with the different styles of faceting. Why do people go these great lengths? Because we have a fabulous material that refracts light inside.
Reliability Of Origin Determination For Gemstones
(via Gemological Digest, Vol.3, No.1, 1990) Dr Henry A Hanni writes:
Definition: Origin = geographical place where a gemstone is situated.
This is either the primary deposit in the parent rock or a secondary deposit where the gemstones have been accumulated after decomposition of the parent rock. Since the term Burma, Pailin and Kashmir have a geographical meaning, they should not be used to express a gemstone color type, because it is common knowledge that a particular deposit may produce different shades of colors, some of which may be found in other deposits, as well.
The need for certification of a gemstone’s origin seems to be limited to only a few species or varieties of gems, and to a small group of quite famous deposits. In certain cases, a cut stone can express its place of origin through its physical and chemical properties and by its inclusions and growth structure, as long as these are clearly distinguishable from all other types. Thus these properties must be unique, either alone or in combination. The greater the number of individual and characteristic properties found in a particular stone, the more reliable is the determination of origin. Valuable characteristics should not only positively testify to a certain origin, but the same time excludes other origin possibilities.
Because of the above, experts involved in origin determination must be aware not only of the properties and characteristics of gems from famous sources, but of the properties and characteristics of all other similar sources. Only the exclusive features, those which are unique to a particular deposit can be called diagnostic properties.
Depending on the complexity of the formation of the gem crystals and on the geologic environment, the type and number of characteristics can be quite varied. Formation of gems requires some indispensable main conditions without which the gem cannot grow, as well as side conditions which can influence the growth but are not essential to the growth. Some of these main and minor conditions which can influence the properties and characteristics of gems include:
- availability of the main constituent chemical elements, and the growth speed.
- the types of available trace elements, and their concentrations.
- transport processes and the transport media involved.
- the type of energy source involved in formation (intrusive pegmatite, metamorphic, etc.)
- pressure from free oxygen.
- cooling rate after formation.
- deformation history of the parent rock and the growing crystal.
- protogenetic inclusions, reflecting the parent rock.
- syngenetic inclusions, reflecting the transport medium and genetic formation type.
All of these factors can influence the individual characteristics of a gemstone crystal, resulting in differences in:
- the size and shape of crystals, and their growth zoning.
- color, color homogeneity, color variations.
- trace element mixture (including invisible trace elements).
- solid inclusions and twinning.
- the state of healed fissures (i.e. fingerprints), geometry and degree of restoration.
- nature of fillings in negative crystal voids.
- composition of fluid inclusions.
What sort of diagnostic origin information can we collect from a cut gemstone?
Characteristic features:
- Microscopic investigation
Color and growth zoning relative to the crystallographic structure, color inhomogeneity, twinning type (s), internal strain, observation of type and distribution of solid and fluid/gas inclusions, type of healing fissures.
- Physical and optical properties
Specific gravity, refractive indices, double refraction (birefringence), fluorescent behavior, absorption spectroscopy (UV, VIS, IR), spin resonance spectroscopy, composition of fluids and minimum temperature/pressure estimation (heat/freezing stage microscope).
- Chemical determination
Trace element determination by energy dispersive x-ray fluorescence analysis (EDS-XFA), amount or relative ratio of trace elements present (e.g. Ti, Fe, Cr, V, Ga, etc.), chemical analysis of inclusions by electron beam instruments (scanning electron microscope, electron microprobe).
Some of the observed and collected characteristics are not restricted to a certain deposit, but in combination may be of diagnostic value. Those observations which are unique for a special deposit are the most important diagnostic features in regard to origin determination. Successful origin determination involves the following steps:
Observation → Comparison → Interpretation
↑ ↑ ↑
Scrutiny Comprehension Prudence
How can we get reliable basic knowledge about materials of definite known origin?
The most simple answer to this question is to collect samples directly at the mine or source. In many cases, though, this is not possible, since the source may be exhausted, or located in an inaccessible location. Therefore we must collect our reference material from a safe source, like a museum, an old collection, etc. Information on gemstone sources can also be obtained from books and publications. Many historical gemstone sources are discussed in reference books. Geographical maps give specific information on the type of deposit, scientific publications reveal the properties of the respective material, chemical analyses of the gemstones and their inclusions are published. All observations must be in agreement with the known facts, e.g. trace elements with spectroscopic analyses, inclusions with geology, etc.
From all this information we gain a very complex view of a gemstone deposit and its production. The more material we investigate, the more dense our network becomes. We are even able to add new observations to the earlier information, building upon it. Sharing and discussing new information with knowledgeable colleagues in the same field provides an added check to our results. But it is still important to revise and recheck the fundamentals of the science by basic research and study of the literature for information on new sources and new techniques. Stagnation is dangerous.
Limitations in the determination of origin
As I have pointed out at the beginning, we use differences in properties as a means of discrimination. Properties which are repeated in stones from more than one source are not valued as diagnostic characteristics, but can nevertheless be helpful in excluding other localities which do not possess these properties. As an example, a certain shade of blue does not prove a certain origin, nor does a misty turbidity. But the misty turbidity in combination with the absence of rutile needles points towards a group of possible origins and excludes some other possibilities of sapphire origins. Within the group of possible origins we may come to a definite source, as long as the stone itself contains enough further evidence pointing towards its origin. It may, for example, exhibit a distinctive absorption curve or spectrum never seen in stones from other localities. At the same time it may show included crystals (identified by an electron beam instrument, which are found only that specific source. These inclusions would, therefore, exclude all other source possibilities.
Origin determination done by the SSEF are not dependent upon a single characteristics only, but are based on at least three independent diagnostic features. Our possibilities are restricted if:
- the properties found in an individual stone may also be found in stones from several localities.
- the stone is found to be free from diagnostic features.
- the possible tests which can be performed is reduced, as, for example, in mounted stones.
- the knowledge base on the type of stone being tested is not broad enough.
Sometimes gemstone deposits and mining areas cross geographic borders, such as the corundum deposits in Kenya/Tanzania and Thailand/Cambodia. In many cases, a producing country may contain different deposits which also vary from one another in the characteristics of the stones produced, such as the corundum deposits in Sri Lanka and Montana (USA).
Many persons in the gem trade have far too little knowledge of the actual range of material coming from particular sources. Even within a single mine, the stones can vary in size, color, transparency and therefore, quality, considerably. This fact must be kept in mind when associating a certain stone with a particular group. It is certainly not the overall appearance visible to the naked eye or with a hand lens which decides the origin of a stone. A possible origin is, on the contrary, proved only by a most careful investigation of all the properties and characteristics carried out by an experienced gemologist using modern scientific equipment. And if there is any doubt or ambiguity, an independent and serious scientist would not issue the report. I would appreciate it very much if the current and future customers of SSEF would understand and accept this policy, especially in cases where our result does not conform with your expectations. In some cases we cannot issue a certificate of origin; in others it turns out differently than what you expected.
I hope to have illustrated by this contribution the possibilities, techniques and the philosophy which governs our work at SSEF, regarding both colored gem reports and, as a supplement, the indications of origin.
We are currently using two different types of phrases when we issue an origin report at SSEF. If the stone shows commonly known and widely accepted diagnostic features, leading us to be very certain of the origin, we make the following statement on the report:
According to your request for an indication of origin, we confirm that the ruby described in the gemstone report mentioned above, shows inclusions as well as physical and chemical properties which, based on present gemological knowledge, are characteristic of a ruby from Burma.
In cases where the stone contains, among commonly accepted characteristic features, those recently observed and certified in our laboratory but not yet published, we use the following expression:
According to your request for an indication of origin, we confirm that the sapphire described in the gemstone report mentioned above, shows inclusions as well as physical and chemical properties, which, in our opinion, are characteristic of a sapphire from Kashmir.
I add to this letter a couple of document copies related with origin determination from SSEF. These contain all cases, including treated stones. I hope they are useful for your work. But again I want to stress that it is the trade who wants us to do these origin determinations. Personally I would prefer to omit origin designations, since they do not prove a certain quality or color of a stone. On the other hand, the buyer should be responsible for what he is spending his money on. He should take care by himself and provide his own basic knowledge, not depending only on the merchant’s or seller’s opinion.
Definition: Origin = geographical place where a gemstone is situated.
This is either the primary deposit in the parent rock or a secondary deposit where the gemstones have been accumulated after decomposition of the parent rock. Since the term Burma, Pailin and Kashmir have a geographical meaning, they should not be used to express a gemstone color type, because it is common knowledge that a particular deposit may produce different shades of colors, some of which may be found in other deposits, as well.
The need for certification of a gemstone’s origin seems to be limited to only a few species or varieties of gems, and to a small group of quite famous deposits. In certain cases, a cut stone can express its place of origin through its physical and chemical properties and by its inclusions and growth structure, as long as these are clearly distinguishable from all other types. Thus these properties must be unique, either alone or in combination. The greater the number of individual and characteristic properties found in a particular stone, the more reliable is the determination of origin. Valuable characteristics should not only positively testify to a certain origin, but the same time excludes other origin possibilities.
Because of the above, experts involved in origin determination must be aware not only of the properties and characteristics of gems from famous sources, but of the properties and characteristics of all other similar sources. Only the exclusive features, those which are unique to a particular deposit can be called diagnostic properties.
Depending on the complexity of the formation of the gem crystals and on the geologic environment, the type and number of characteristics can be quite varied. Formation of gems requires some indispensable main conditions without which the gem cannot grow, as well as side conditions which can influence the growth but are not essential to the growth. Some of these main and minor conditions which can influence the properties and characteristics of gems include:
- availability of the main constituent chemical elements, and the growth speed.
- the types of available trace elements, and their concentrations.
- transport processes and the transport media involved.
- the type of energy source involved in formation (intrusive pegmatite, metamorphic, etc.)
- pressure from free oxygen.
- cooling rate after formation.
- deformation history of the parent rock and the growing crystal.
- protogenetic inclusions, reflecting the parent rock.
- syngenetic inclusions, reflecting the transport medium and genetic formation type.
All of these factors can influence the individual characteristics of a gemstone crystal, resulting in differences in:
- the size and shape of crystals, and their growth zoning.
- color, color homogeneity, color variations.
- trace element mixture (including invisible trace elements).
- solid inclusions and twinning.
- the state of healed fissures (i.e. fingerprints), geometry and degree of restoration.
- nature of fillings in negative crystal voids.
- composition of fluid inclusions.
What sort of diagnostic origin information can we collect from a cut gemstone?
Characteristic features:
- Microscopic investigation
Color and growth zoning relative to the crystallographic structure, color inhomogeneity, twinning type (s), internal strain, observation of type and distribution of solid and fluid/gas inclusions, type of healing fissures.
- Physical and optical properties
Specific gravity, refractive indices, double refraction (birefringence), fluorescent behavior, absorption spectroscopy (UV, VIS, IR), spin resonance spectroscopy, composition of fluids and minimum temperature/pressure estimation (heat/freezing stage microscope).
- Chemical determination
Trace element determination by energy dispersive x-ray fluorescence analysis (EDS-XFA), amount or relative ratio of trace elements present (e.g. Ti, Fe, Cr, V, Ga, etc.), chemical analysis of inclusions by electron beam instruments (scanning electron microscope, electron microprobe).
Some of the observed and collected characteristics are not restricted to a certain deposit, but in combination may be of diagnostic value. Those observations which are unique for a special deposit are the most important diagnostic features in regard to origin determination. Successful origin determination involves the following steps:
Observation → Comparison → Interpretation
↑ ↑ ↑
Scrutiny Comprehension Prudence
How can we get reliable basic knowledge about materials of definite known origin?
The most simple answer to this question is to collect samples directly at the mine or source. In many cases, though, this is not possible, since the source may be exhausted, or located in an inaccessible location. Therefore we must collect our reference material from a safe source, like a museum, an old collection, etc. Information on gemstone sources can also be obtained from books and publications. Many historical gemstone sources are discussed in reference books. Geographical maps give specific information on the type of deposit, scientific publications reveal the properties of the respective material, chemical analyses of the gemstones and their inclusions are published. All observations must be in agreement with the known facts, e.g. trace elements with spectroscopic analyses, inclusions with geology, etc.
From all this information we gain a very complex view of a gemstone deposit and its production. The more material we investigate, the more dense our network becomes. We are even able to add new observations to the earlier information, building upon it. Sharing and discussing new information with knowledgeable colleagues in the same field provides an added check to our results. But it is still important to revise and recheck the fundamentals of the science by basic research and study of the literature for information on new sources and new techniques. Stagnation is dangerous.
Limitations in the determination of origin
As I have pointed out at the beginning, we use differences in properties as a means of discrimination. Properties which are repeated in stones from more than one source are not valued as diagnostic characteristics, but can nevertheless be helpful in excluding other localities which do not possess these properties. As an example, a certain shade of blue does not prove a certain origin, nor does a misty turbidity. But the misty turbidity in combination with the absence of rutile needles points towards a group of possible origins and excludes some other possibilities of sapphire origins. Within the group of possible origins we may come to a definite source, as long as the stone itself contains enough further evidence pointing towards its origin. It may, for example, exhibit a distinctive absorption curve or spectrum never seen in stones from other localities. At the same time it may show included crystals (identified by an electron beam instrument, which are found only that specific source. These inclusions would, therefore, exclude all other source possibilities.
Origin determination done by the SSEF are not dependent upon a single characteristics only, but are based on at least three independent diagnostic features. Our possibilities are restricted if:
- the properties found in an individual stone may also be found in stones from several localities.
- the stone is found to be free from diagnostic features.
- the possible tests which can be performed is reduced, as, for example, in mounted stones.
- the knowledge base on the type of stone being tested is not broad enough.
Sometimes gemstone deposits and mining areas cross geographic borders, such as the corundum deposits in Kenya/Tanzania and Thailand/Cambodia. In many cases, a producing country may contain different deposits which also vary from one another in the characteristics of the stones produced, such as the corundum deposits in Sri Lanka and Montana (USA).
Many persons in the gem trade have far too little knowledge of the actual range of material coming from particular sources. Even within a single mine, the stones can vary in size, color, transparency and therefore, quality, considerably. This fact must be kept in mind when associating a certain stone with a particular group. It is certainly not the overall appearance visible to the naked eye or with a hand lens which decides the origin of a stone. A possible origin is, on the contrary, proved only by a most careful investigation of all the properties and characteristics carried out by an experienced gemologist using modern scientific equipment. And if there is any doubt or ambiguity, an independent and serious scientist would not issue the report. I would appreciate it very much if the current and future customers of SSEF would understand and accept this policy, especially in cases where our result does not conform with your expectations. In some cases we cannot issue a certificate of origin; in others it turns out differently than what you expected.
I hope to have illustrated by this contribution the possibilities, techniques and the philosophy which governs our work at SSEF, regarding both colored gem reports and, as a supplement, the indications of origin.
We are currently using two different types of phrases when we issue an origin report at SSEF. If the stone shows commonly known and widely accepted diagnostic features, leading us to be very certain of the origin, we make the following statement on the report:
According to your request for an indication of origin, we confirm that the ruby described in the gemstone report mentioned above, shows inclusions as well as physical and chemical properties which, based on present gemological knowledge, are characteristic of a ruby from Burma.
In cases where the stone contains, among commonly accepted characteristic features, those recently observed and certified in our laboratory but not yet published, we use the following expression:
According to your request for an indication of origin, we confirm that the sapphire described in the gemstone report mentioned above, shows inclusions as well as physical and chemical properties, which, in our opinion, are characteristic of a sapphire from Kashmir.
I add to this letter a couple of document copies related with origin determination from SSEF. These contain all cases, including treated stones. I hope they are useful for your work. But again I want to stress that it is the trade who wants us to do these origin determinations. Personally I would prefer to omit origin designations, since they do not prove a certain quality or color of a stone. On the other hand, the buyer should be responsible for what he is spending his money on. He should take care by himself and provide his own basic knowledge, not depending only on the merchant’s or seller’s opinion.
Wednesday, May 09, 2007
Harry’s First Big Deal
(via Indiaqua, 49/1988; Extracted from ‘M’ The Civilized Man, 1985)
Harry Oppenheimer’s first deal involved one of the last of the big time eccentric prospectors. John Williamson, a one time Anglo employee who had wandered off in search of his dream mine and, in 1940, found the Mwadui mine, one of the richest diamond pipes ever discovered, in Tanganyika.
An independent sort, he treated his mine like a sovereign state, even flying his own flag with his initials on it overhead. And shortly after he went into production, he pulled his diamonds out of the syndicate’s distribution system, saying he could make more selling them himself.
“Well, he got his desire and found his mine, and he became very rich,” Oppenheimer recalls, “but in the course of this he simply destroyed his health and took to drink in a major way. He was not the sort of person who drinks too much at dinner, then goes to bed and suddenly drinks a case of whiskey. But he was an attractive fellow, inspired loyalty in his people. He didn’t form a company sell his shares; he owned the whole thing, and lived on the mine.”
There he built his own little paradise; a home filled with fine antiques and first editions—and mongrel dogs everywhere. Williamson took up knitting, and twice in a row won the Aylesbury Women’s Institute Silver Distaff Award for needlework. He liked to tell visitors that diamonds were so abundant at Mwadui they could find them lying on the ground. Inevitably, someone would find a huge pink diamond, only to learn it was a plastic replica of the 54 carat stone Williamson had given Princess Elizabeth as a wedding present. He also like to carry scissors in his pocket to snip off people’s ties.
Shortly after the war, Harry was assigned by his father to bring Mwadui, and this character, back into the fold. “I did establish quite a relationship with him, and I think that was because I happened to like him, “he says. “But he was the sort of person who, if you talked to him about business matters, you had to proceed very slowly. If you said anything quickly……it was as though you had a rather nice wild animal but if you move quickly, it sort of take frights.”
At one negotiating meeting in Williamson’s office, Oppenheimer determined not to say anything until Williamson known for his long, unexplainable silences, spoke first. Oppenheimer gave up after 20 minutes. Eventually, however, he did succeed in getting a new contract for Williamson’s production.
“Finally he died,” says Oppenheimer, “and he left the mine to his family, left control of it to his brother Percy, who was a garage proprietor in Edmonton (Ontario). And this fellow, there was no vice in him at all, but he was entirely unsuited to such a thing; he found tropical Tanzania much less agreeable than living among the snows of Edmonton. Finally I went up there and we bought the mine. “Bought it, that is, with a sales contract that he drew up himself on the spot, without the aid of company lawyers.
Harry Oppenheimer’s first deal involved one of the last of the big time eccentric prospectors. John Williamson, a one time Anglo employee who had wandered off in search of his dream mine and, in 1940, found the Mwadui mine, one of the richest diamond pipes ever discovered, in Tanganyika.
An independent sort, he treated his mine like a sovereign state, even flying his own flag with his initials on it overhead. And shortly after he went into production, he pulled his diamonds out of the syndicate’s distribution system, saying he could make more selling them himself.
“Well, he got his desire and found his mine, and he became very rich,” Oppenheimer recalls, “but in the course of this he simply destroyed his health and took to drink in a major way. He was not the sort of person who drinks too much at dinner, then goes to bed and suddenly drinks a case of whiskey. But he was an attractive fellow, inspired loyalty in his people. He didn’t form a company sell his shares; he owned the whole thing, and lived on the mine.”
There he built his own little paradise; a home filled with fine antiques and first editions—and mongrel dogs everywhere. Williamson took up knitting, and twice in a row won the Aylesbury Women’s Institute Silver Distaff Award for needlework. He liked to tell visitors that diamonds were so abundant at Mwadui they could find them lying on the ground. Inevitably, someone would find a huge pink diamond, only to learn it was a plastic replica of the 54 carat stone Williamson had given Princess Elizabeth as a wedding present. He also like to carry scissors in his pocket to snip off people’s ties.
Shortly after the war, Harry was assigned by his father to bring Mwadui, and this character, back into the fold. “I did establish quite a relationship with him, and I think that was because I happened to like him, “he says. “But he was the sort of person who, if you talked to him about business matters, you had to proceed very slowly. If you said anything quickly……it was as though you had a rather nice wild animal but if you move quickly, it sort of take frights.”
At one negotiating meeting in Williamson’s office, Oppenheimer determined not to say anything until Williamson known for his long, unexplainable silences, spoke first. Oppenheimer gave up after 20 minutes. Eventually, however, he did succeed in getting a new contract for Williamson’s production.
“Finally he died,” says Oppenheimer, “and he left the mine to his family, left control of it to his brother Percy, who was a garage proprietor in Edmonton (Ontario). And this fellow, there was no vice in him at all, but he was entirely unsuited to such a thing; he found tropical Tanzania much less agreeable than living among the snows of Edmonton. Finally I went up there and we bought the mine. “Bought it, that is, with a sales contract that he drew up himself on the spot, without the aid of company lawyers.
Colored Stone Grading—To Be Or Not To Be
2007: Still there are no international standards for colored stone grading. Much work remains to be done.
(via Gemological Digest, Vol.2, No.3, 1998) Richard Hughes writes:
To mention the subject of colored stone grading to many gem dealers is to tell a Jew that Hitler was a great humanitarian—they immediately begin to foam at the mouth, snarling and growling in your general direction. A touchy subject? Not at all. Just don’t drop in into your conversation upwind of an ICA congress. Well, at the risk of getting bitten, I would still like to say a few words on the subject of colored stone grading.
The idea of grading gemstones is as old as the gem business itself. Learning to separate gems into different quality categories is one of the first things learned by most gem dealers and, in fact, their success in business rides to a large degree on their ability to do just that. However, idea of gem labs grading colored gemstones for the trade and public was first realized only in the late 1970s. This coincided with a general boom in the colored market. All booms, though, are usually followed by busts, at least in business. When this occurred in the early to mid 1980s, many dealers pointed at colored stone grading by labs as the major culprit. I do not believe that this is entirely a fair assessment. The issuance of grading reports by labs may have been responsible for part of the downturn, but they were certainly not the major cause.
Early attempts at laboratory grading were (and still are) crude, at best. This is true in the development of anything that is new. If you were to look back at first airplanes you would see that they were hardly satisfactory. Clumsy and dangerous, they often crashed and killed their occupants. Even today crashes occur. Airplanes remain far from perfect and probably never will be. Few people today would argue against their use on that score, but in the beginning many did. ‘Man should not attempt to fly. It is against God’s will. If man were meant to fly, God would have given him wings.’ I guess if man were meant to drive, he should have been born with wheels and horn, too.
Due to the primitive state of colored stone grading today, many dealers have stated that this subject is beyond the ability of humans to resolve (I must confess that I too once held this opinion because of the many difficulties involved). The grading of colored stones is so complex that it can never be summarized on a short report, they claim. When I hear this argument I am reminded of some of the books written on opal prior to 1965. Certain authors (Eyles, W.C., 1964), in discussing the play of color effect seen in opal, stated that it was a mystery that would probably never be solved by humans. For this reason, they claimed opal would never be synthesized. In 1965, however, scientists did discover the cause of this play of color and only six months later these same scientists had produced the first synthetic opal. The lesson here is not to just say no, to paraphrase Nancy Reagan, but instead, to never say never. What is needed is to less science, but more decent science.
I will be the first to admit that colored stone grading (and diamond grading) as practiced today is extremely unreliable and, in my opinion, not reproducible within a reasonable degree of error. I do not believe that any of the labs issuing these reports today (for anyone else, myself included, for that matter) have a firm enough grasp of the subject to do a good job of it. Colored stone grading today is comparable to the airplanes of 1910. Crashes occur far too frequently, and anyone who is offered a ride should definitely be warned of the considerable risks involved. Labs (and appraisers) which do not warn their customers of these risks are guilty of negligence, pure and simple. Too often these risks are swept under the carpet. Of course, you may argue that one does not learn to fly by remaining on the ground, and this is perfectly true. But it seems rash to be taking on passengers, unless they are properly informed of the risks. By risks, I refer to the degree of reproducibility of the grades. This should be clearly stated on the document, both for colored stone grading and diamond grading reports. If the risks are clearly described, however, I see nothing wrong with issuing these reports.
I must confess that the organization I work for, AIGS, also issued colored stone grading reports at one time. We no longer to so, mostly for the reason stated above—lack of a reasonable degree of reproducibility of the grades. We believe that there is still much to be learned about colored stone grading.
The trade’s inability to produce a high standard colored stone grading today does not mean that it should abandon the idea altogether. That would be akin to throwing out the baby with the bath water. The benefits of accurate grading system are too great to quit at the first sign of problems. Instead, we must keep working to develop and refine the grading techniques so that they can be made more reproducible.
Change inevitably brings about certain uneasiness in people, particularly as they age. Some feel this more than others. Many colored stone dealers have considered the changes in the business wrought by the introduction of diamond and colored stone grading reports and have deplored them. Some of the major criticisms leveled against colored stone grading by labs were discussed in 1985 by Reuven Sadkiel (Gemwatch, Feb, 1986), the President of the Israel Precious Stones and Diamonds Exchange. In his 1985 address to the Second European Precious Stones Congress in Antwerp, Sadkiel described colored stone grading by labs in the following terms:
1. It takes the factor of color appreciation and preference away from human taste and senses and replaces it with the judgment of a technical device.
2. It brings us to an artificial and unreal rating of what are supposedly the preferred color ranges.
3. It may bring about a stepped-up demand for certain colors, which are considered preferred when their availability in nature is rather rare.
4. It is absolutely unrealistic to impose a scientific conclusive scale of color preferences when in practice the desirability of color is a matter of personal taste and the natural daylight conditions in different geographic regions greatly influence the perception of color. The same stone has a different color appearance in different regions.
5. Grading and rating systems will cancel the element of illusion which is familiar to all of us, the all important subjective beauty and attraction of a specific rough or cut stone. An appreciation of the stone based on the skills, experiences and professionalism gained by the dealers over many years will become irrelevant the moment a mechanical device establishes a rating and value for the stone.
6. And, perhaps most disturbingly, the trade will de facto transfer the responsibility of setting the value of the goods we deal in to outside gemologists, laboratories, and their devices.
In conclusion, I want to restate unequivocally that it is impossible to allow the trade to accept color grading systems, even if they may seem helpful or practical. These grades will lead to value ratings and preference scales—which totally contradict the market realities which characterize our trade. It will lead first to trading with certificates and eventually to trading in certificates. It will eliminate the special role of dealers in the precious stone business. It will transfer the decision as to prices and preferences from the markets to the laboratories. It will destroy the norms and principles under which the business has flourished for many generations. It will take away the element of illusion, one of the most beautiful aspects of the trade. It will lead our business into chaos. It is up to us to avoid all this by saying ‘no’ to color rating systems.
After reading the above, one may wonder whether, in the opinion of Mr Sadkiel, colored stone grading might also cause hair to grow on the palms of one’s hand. Seriously, I do believe that a number of Mr Sadkiel’s criticisms have a certain amount of truth to them. But at the same time they do not tell the whole story.
Colored stone dealers today often see themselves as the last of the great adventurers, considering that they are among the first travelers to make the journey East since the time of Marco Polo. American dealer, Ray Zajicek, summed up this attitude when he said, “The colored stone dealer must go all over the world to seek his gems, sometimes imperiling his life in distant places such as Africa, South America and Southeast Asia.” (Everhart, 1987). Traveling to foreign lands to obtain the goods, they often visit areas which ordinary tourists shun. And similar to the European travelers of the Middle Ages, they often exaggerate the dangers of such travels. During the Middle Ages, European travelers to Asia often returned with fanciful accounts of their journeys. Dragons, mountains that spit fire, yetis, etc., were said to be the dangers of Asian travel during these times. Today these have replaced by smuggling, difficult access to mining areas, local wars, and simple culture shock at that. The purpose of such stories, I believe, is two fold. First, they tend to discourage any would be competitors, by representing the journeys as being much more hazardous than they actually are. Secondly, they lend a certain romance, or illusion, if you will, to the profession. Many gem dealers believe that colored stone grading would somehow remove this aspect of the trade, but this is not necessarily so.
The important thing to remember about colored stone grading is that it is a creation of humans, and so can be made to be anything that we want it to be. It is not, and should not be, a static entity created in a vacuum. A useable colored stone grading language can only be created by combining the scientific expertise of gemologists and other scientists with the practical expertise of the dealers. If the experts (i.e., dealers) believe the romance factor to be important and essential to the business, then there is no reason why it could not be incorporated into the grading. An additional romance grade could be added to the report. Perhaps gems mined or purchased in countries where a guerilla war is currently underway could be given five bonus points. Are their bandits along the access roads to mines? That would certainly worth a few extra points. Mines located above 4000 meters elevation might fetch ten extra points. Is there a language problem or do the taxi drivers overcharge you in the place where the gems are bought? Separate categories could be created for each of these (of course, a negative scale might also be needed. Male buyers making their purchase in Bangkok, famous for its active nightlife, generally enjoy themselves quite a bit while there, and so, logically, would be penalized. This, however, would not apply to female buyers, at least in Bangkok). The bottom line is that colored stone grading can incorporate anything that we want in to.
Similarly, the idea of different lighting conditions in different parts of the world can also be addressed. Studies can be undertaken to discern exactly what these differences are, or if, in fact, they exist at all. I, myself, as with most dealers, believe that these differences do exist, but until the problem is studied in more detail it would seem somewhat rash to say absolutely that they are detectable (let us not forget that, up until recently, most experts believed the world to be flat). If these differences are found to be important, they can then be incorporated into the report. Regional reports can be made for individual areas where the stone is going to be sold. However, to state that these differences will never be quantifiable is, in my opinion, shortsighted.
One of the biggest problems that we at AIGS have found in developing an effective colored stone grading language is that many experts (i.e. dealers) do not understand color terminology, as used by color scientists in other fields. An example of this is given by common dealer descriptions of rubies. If one asks an average dealer what the difference is between Burmese and Thai rubies, most will tell you that Thai ruby is too purple in terms of its hue positions. In fact, we have found that most Burmese rubies are more purple than their Thai counterparts.
The real difference between a fine ruby and a poor one is the saturation (intensity) of the hue rather than a shift in the hue position itself. We have found this to be the case with most colored stones. Too often dealers tend to refer to differences in color between one gem and another solely in terms of hue position, when saturation differences are the crucial factor. Certainly, an important factor in developing an effective colored stone grading language will be reaching agreement among both dealers and gemologists as to the proper vocabulary to be used in describing the appearance of the stones. And it is the overall appearance of the stone that is the crux of the issue here, not just the gem’s color.
As to market tastes in different countries, most dealers state that appreciation of color varies from one country to another. Colored stone grading reports, it is claimed, would dictate to the market which color is best, rather than the market making this decision. This is not necessarily so. True, certain markets tend to purchase certain colors over others, but I’ve observed that there is general agreement among connoisseurs as to what constitutes the best or better colors. Consequently, these better colors consistently fetch the highest prices in the market. As for the lower grades, yes, certain colors are purchased more for certain markets than for others. Rather than being a disagreement as to what is best, however, it is more a function of the buying power of the customers in that market. For example, Swiss buyers of corundum consistently purchase the better (i.e. more expensive) grades because their customers are generally more wealthy and so can afford to buy the best. In contrast, buyers from England must sell to customers in a market where the economy is depressed, and so are forced to settle for stones of lower quality. This is not to say that the people in England prefer to buy the lower grades. They just do not have enough money to purchase the best. The point here, and it is an important one, is that buyers will purchase the qualities which are most easily saleable in their home markets. Some may say that the English prefer darker rubies, while the Japanese prefer more pinkish stones. It is not that the Japanese and English buyers cannot agree upon what is best. They can. If given an unlimited amount of money to spend and if offered to a broad selection of rubies where side by side comparisons can be made, virtually all experienced buyers will choose the same stone almost every time. That is why these top quality stones fetch the highest prices in the Bangkok market.
One of Mr Sadkiel’s major objections to colored stone grading by labs was that it might bring about a stepped up demand for certain colors which are considered preferred when their availability in nature is rather rare. I fail completely to see the logic in this argument. Should we avoid telling people that Picasso and Van Gogh were great artists simply because they didn’t produce enough paintings to put one in everybody’s home? I think not.
It is interesting to note that the highest prices for the very best qualities are usually paid in the producing country itself. This is because the dealers in the country where the gem is found almost always have the most experience in buying that stone. They know the full range of qualities possible for that stone and so are better able to recognize the very top quality when it is shown to them. This may seem to contradict what I have just said about all experienced dealers agreeing on what is the best quality. The problem here is that the color memory of humans is extremely poor. Given side by side comparisons, humans are able to differentiate literally millions of colors. This ability shrinks very quickly, however, if the colors are examined one at a time. With colored gemstones, it is often not possible to make side by side comparisons—especially for the best qualities, due to their great rarity. Thus, dealers are forced to rely upon their memories when making a decision as to just where a particular stone lies within the color quality spectrum (many dealers carry with them reference stones for this purpose, because human color memory is so unreliable). Dealers in the producing countries have the most experience in judging that particular variety, and so are better able to place an individual stone in its proper rank within the spectrum. Were side-by-side comparisons are possible, dealers in the producing countries would not necessarily have such an advantage. Again, in side-by-side comparisons, my experience is that there is agreement as to which stone has the best color, even among dealers from many different countries.
The lesson to be learned here for those involved in colored stone grading is that, since side-by-side comparisons for the very rare top grades are not often possible, it will be necessary to come up with some other calibrated references (such as the GIA’s ColorMaster), as well as to consult with the most experienced dealers to determine just what constitutes the best for each individual variety. These dealers will generally not be found in the consuming countries, but instead, in the producing countries themselves.
True understanding of all colored stones is much too complex for this knowledge to be gathered into the head of a single person. Instead, I believe that increasing specialization will be required. It we want to learn and define what is best in corundum, we must go to Thailand, Burma, Sri Lanka, India, Australia and East Africa. If we want to learn what is best in emerald, we must seek out experts in Colombia, Zambia, Israel, Brazil, India, Pakistan and Afghanistan. If we want to learn what is best in Jade, we must seek out experts in Burma, China, Thailand, Hong Kong and Taiwan. These are the experts who are most qualified to judge what is best, because it is they who have the most experience in examining that particular type of stone.
Because of the tremendous difficulties involved in assimilating all of this expertise from such widely ranging sources, great mistakes in grading have occurred in the past. Many dealers are familiar with the mistakes in grading rubies made by AGL (American Gemological Laboratories) in New York during the early 1980s. Their grading of rubies was based mainly upon the hue position of the stone, in part because of the incorrect terminology used by dealers in describing such stones. As I stated earlier, dealers often describe color differences solely in terms of hue position when saturation is actually the key. Burmese rubies are said to be more red, while Thai rubies are described as being too purple. Actually, the reverse is true. The result of this lack of a properly defined color vocabulary was that AGL awarded its highest color grades to the dark Thai rubies which were the purest red in hue position (AIGS Type D, daeng dum). Burmese rubies, which have traditionally fetched the highest prices in the market (due largely to their higher saturation of color), were given lower grades because they were more purple in hue position.
Dealers quickly picked up on this discrepancy and began buying up these dark red rubies in Thailand where they were relatively cheap compared with Burmese stones, because they were graded highest in New York at AGL. Eventually AGL realized its mistake and corrected the situation, but not before considerable damage was done. To reiterate, for an effective colored stone grading language to be developed, it will require both scientific expertise as well as dealer expertise. And the dealer expertise is generally greatest at source, not just in the consuming countries.
Assimilating the knowledge from experts at the source is certainly one of the most difficult tasks facing the trade in the development of an effective colored stone grading system. There does appear, however, to be some promise for the future. Specifically what I am referring to is the establishment of gemological institutes and journals in the producing nations. The first such institute in a major producing country was the founding of AIGS in Bangkok ten years ago. Its success should provide a model for similar institutes in other producing nations.
During the nineteenth century the British were able to glean and distribute a tremendous amount of information about Asian countries and their cultures by establishing Asiatic Societies and their associated journals in a number of Asian nations. These societies provided the framework for a direct exchange of information pertaining to Asia and the rest of the world. Similarly, AIGS and this journal will also allow information about Asian gems to be distributed from the source to the rest of the world. What is needed now are similar institutes and associated publications in other major producing and trading centers. India and Sri Lanka have recently founded gemological journals which provide both fascinating and useful information about their markets. The Sauer family and others are presently working to establish an institute along the lines of AIGS in Brazil. We need institutes and journals in Burma, Colombia, China, Kenya, Tanzania, Zambia, Pakistan, Afghanistan, Nigeria, Mexico, in all the places where gems are produced. This is the only way in which the rest of the world can tap into that special knowledge and expertise that is available at the source. I am not trying to discount the importance of the work done by GIA, AGL, AGMS, DgemG, GAGB, GAA, CGA, SSEF, GAAJ, AFG, Gubelin, and others in the consuming nations. These organizations will continue to be essential in the future development of colored stone grading, particularly with regard to new and improved technologies. Today, however, very little information is being disseminated from the producing nations themselves. We must find a way to tap into the expertise at the source. Establishment of institutes and journals in the producing nations offers the most viable means of accomplishing this goal.
In summary, it is clear that much remains to be learned about colored stone grading, much work remains to be done. This will require cooperation among dealers and gemologists. Each has something to learn. Rather than looking upon one another as adversaries, let us look upon each other as colleagues, sharing in the development of something exciting, something new. Rather than looking wishfully back at the past, let us look forward to the future. Colored stone grading is here to stay, no matter how much some people might wish otherwise, because the consumers want it. And our trade exists for the consumers. They are the ones who buy our product. A great adventure awaits us. Colored stone grading can be anything that we make it. Let us work together, dealers and gemologists, to make it right.
(via Gemological Digest, Vol.2, No.3, 1998) Richard Hughes writes:
To mention the subject of colored stone grading to many gem dealers is to tell a Jew that Hitler was a great humanitarian—they immediately begin to foam at the mouth, snarling and growling in your general direction. A touchy subject? Not at all. Just don’t drop in into your conversation upwind of an ICA congress. Well, at the risk of getting bitten, I would still like to say a few words on the subject of colored stone grading.
The idea of grading gemstones is as old as the gem business itself. Learning to separate gems into different quality categories is one of the first things learned by most gem dealers and, in fact, their success in business rides to a large degree on their ability to do just that. However, idea of gem labs grading colored gemstones for the trade and public was first realized only in the late 1970s. This coincided with a general boom in the colored market. All booms, though, are usually followed by busts, at least in business. When this occurred in the early to mid 1980s, many dealers pointed at colored stone grading by labs as the major culprit. I do not believe that this is entirely a fair assessment. The issuance of grading reports by labs may have been responsible for part of the downturn, but they were certainly not the major cause.
Early attempts at laboratory grading were (and still are) crude, at best. This is true in the development of anything that is new. If you were to look back at first airplanes you would see that they were hardly satisfactory. Clumsy and dangerous, they often crashed and killed their occupants. Even today crashes occur. Airplanes remain far from perfect and probably never will be. Few people today would argue against their use on that score, but in the beginning many did. ‘Man should not attempt to fly. It is against God’s will. If man were meant to fly, God would have given him wings.’ I guess if man were meant to drive, he should have been born with wheels and horn, too.
Due to the primitive state of colored stone grading today, many dealers have stated that this subject is beyond the ability of humans to resolve (I must confess that I too once held this opinion because of the many difficulties involved). The grading of colored stones is so complex that it can never be summarized on a short report, they claim. When I hear this argument I am reminded of some of the books written on opal prior to 1965. Certain authors (Eyles, W.C., 1964), in discussing the play of color effect seen in opal, stated that it was a mystery that would probably never be solved by humans. For this reason, they claimed opal would never be synthesized. In 1965, however, scientists did discover the cause of this play of color and only six months later these same scientists had produced the first synthetic opal. The lesson here is not to just say no, to paraphrase Nancy Reagan, but instead, to never say never. What is needed is to less science, but more decent science.
I will be the first to admit that colored stone grading (and diamond grading) as practiced today is extremely unreliable and, in my opinion, not reproducible within a reasonable degree of error. I do not believe that any of the labs issuing these reports today (for anyone else, myself included, for that matter) have a firm enough grasp of the subject to do a good job of it. Colored stone grading today is comparable to the airplanes of 1910. Crashes occur far too frequently, and anyone who is offered a ride should definitely be warned of the considerable risks involved. Labs (and appraisers) which do not warn their customers of these risks are guilty of negligence, pure and simple. Too often these risks are swept under the carpet. Of course, you may argue that one does not learn to fly by remaining on the ground, and this is perfectly true. But it seems rash to be taking on passengers, unless they are properly informed of the risks. By risks, I refer to the degree of reproducibility of the grades. This should be clearly stated on the document, both for colored stone grading and diamond grading reports. If the risks are clearly described, however, I see nothing wrong with issuing these reports.
I must confess that the organization I work for, AIGS, also issued colored stone grading reports at one time. We no longer to so, mostly for the reason stated above—lack of a reasonable degree of reproducibility of the grades. We believe that there is still much to be learned about colored stone grading.
The trade’s inability to produce a high standard colored stone grading today does not mean that it should abandon the idea altogether. That would be akin to throwing out the baby with the bath water. The benefits of accurate grading system are too great to quit at the first sign of problems. Instead, we must keep working to develop and refine the grading techniques so that they can be made more reproducible.
Change inevitably brings about certain uneasiness in people, particularly as they age. Some feel this more than others. Many colored stone dealers have considered the changes in the business wrought by the introduction of diamond and colored stone grading reports and have deplored them. Some of the major criticisms leveled against colored stone grading by labs were discussed in 1985 by Reuven Sadkiel (Gemwatch, Feb, 1986), the President of the Israel Precious Stones and Diamonds Exchange. In his 1985 address to the Second European Precious Stones Congress in Antwerp, Sadkiel described colored stone grading by labs in the following terms:
1. It takes the factor of color appreciation and preference away from human taste and senses and replaces it with the judgment of a technical device.
2. It brings us to an artificial and unreal rating of what are supposedly the preferred color ranges.
3. It may bring about a stepped-up demand for certain colors, which are considered preferred when their availability in nature is rather rare.
4. It is absolutely unrealistic to impose a scientific conclusive scale of color preferences when in practice the desirability of color is a matter of personal taste and the natural daylight conditions in different geographic regions greatly influence the perception of color. The same stone has a different color appearance in different regions.
5. Grading and rating systems will cancel the element of illusion which is familiar to all of us, the all important subjective beauty and attraction of a specific rough or cut stone. An appreciation of the stone based on the skills, experiences and professionalism gained by the dealers over many years will become irrelevant the moment a mechanical device establishes a rating and value for the stone.
6. And, perhaps most disturbingly, the trade will de facto transfer the responsibility of setting the value of the goods we deal in to outside gemologists, laboratories, and their devices.
In conclusion, I want to restate unequivocally that it is impossible to allow the trade to accept color grading systems, even if they may seem helpful or practical. These grades will lead to value ratings and preference scales—which totally contradict the market realities which characterize our trade. It will lead first to trading with certificates and eventually to trading in certificates. It will eliminate the special role of dealers in the precious stone business. It will transfer the decision as to prices and preferences from the markets to the laboratories. It will destroy the norms and principles under which the business has flourished for many generations. It will take away the element of illusion, one of the most beautiful aspects of the trade. It will lead our business into chaos. It is up to us to avoid all this by saying ‘no’ to color rating systems.
After reading the above, one may wonder whether, in the opinion of Mr Sadkiel, colored stone grading might also cause hair to grow on the palms of one’s hand. Seriously, I do believe that a number of Mr Sadkiel’s criticisms have a certain amount of truth to them. But at the same time they do not tell the whole story.
Colored stone dealers today often see themselves as the last of the great adventurers, considering that they are among the first travelers to make the journey East since the time of Marco Polo. American dealer, Ray Zajicek, summed up this attitude when he said, “The colored stone dealer must go all over the world to seek his gems, sometimes imperiling his life in distant places such as Africa, South America and Southeast Asia.” (Everhart, 1987). Traveling to foreign lands to obtain the goods, they often visit areas which ordinary tourists shun. And similar to the European travelers of the Middle Ages, they often exaggerate the dangers of such travels. During the Middle Ages, European travelers to Asia often returned with fanciful accounts of their journeys. Dragons, mountains that spit fire, yetis, etc., were said to be the dangers of Asian travel during these times. Today these have replaced by smuggling, difficult access to mining areas, local wars, and simple culture shock at that. The purpose of such stories, I believe, is two fold. First, they tend to discourage any would be competitors, by representing the journeys as being much more hazardous than they actually are. Secondly, they lend a certain romance, or illusion, if you will, to the profession. Many gem dealers believe that colored stone grading would somehow remove this aspect of the trade, but this is not necessarily so.
The important thing to remember about colored stone grading is that it is a creation of humans, and so can be made to be anything that we want it to be. It is not, and should not be, a static entity created in a vacuum. A useable colored stone grading language can only be created by combining the scientific expertise of gemologists and other scientists with the practical expertise of the dealers. If the experts (i.e., dealers) believe the romance factor to be important and essential to the business, then there is no reason why it could not be incorporated into the grading. An additional romance grade could be added to the report. Perhaps gems mined or purchased in countries where a guerilla war is currently underway could be given five bonus points. Are their bandits along the access roads to mines? That would certainly worth a few extra points. Mines located above 4000 meters elevation might fetch ten extra points. Is there a language problem or do the taxi drivers overcharge you in the place where the gems are bought? Separate categories could be created for each of these (of course, a negative scale might also be needed. Male buyers making their purchase in Bangkok, famous for its active nightlife, generally enjoy themselves quite a bit while there, and so, logically, would be penalized. This, however, would not apply to female buyers, at least in Bangkok). The bottom line is that colored stone grading can incorporate anything that we want in to.
Similarly, the idea of different lighting conditions in different parts of the world can also be addressed. Studies can be undertaken to discern exactly what these differences are, or if, in fact, they exist at all. I, myself, as with most dealers, believe that these differences do exist, but until the problem is studied in more detail it would seem somewhat rash to say absolutely that they are detectable (let us not forget that, up until recently, most experts believed the world to be flat). If these differences are found to be important, they can then be incorporated into the report. Regional reports can be made for individual areas where the stone is going to be sold. However, to state that these differences will never be quantifiable is, in my opinion, shortsighted.
One of the biggest problems that we at AIGS have found in developing an effective colored stone grading language is that many experts (i.e. dealers) do not understand color terminology, as used by color scientists in other fields. An example of this is given by common dealer descriptions of rubies. If one asks an average dealer what the difference is between Burmese and Thai rubies, most will tell you that Thai ruby is too purple in terms of its hue positions. In fact, we have found that most Burmese rubies are more purple than their Thai counterparts.
The real difference between a fine ruby and a poor one is the saturation (intensity) of the hue rather than a shift in the hue position itself. We have found this to be the case with most colored stones. Too often dealers tend to refer to differences in color between one gem and another solely in terms of hue position, when saturation differences are the crucial factor. Certainly, an important factor in developing an effective colored stone grading language will be reaching agreement among both dealers and gemologists as to the proper vocabulary to be used in describing the appearance of the stones. And it is the overall appearance of the stone that is the crux of the issue here, not just the gem’s color.
As to market tastes in different countries, most dealers state that appreciation of color varies from one country to another. Colored stone grading reports, it is claimed, would dictate to the market which color is best, rather than the market making this decision. This is not necessarily so. True, certain markets tend to purchase certain colors over others, but I’ve observed that there is general agreement among connoisseurs as to what constitutes the best or better colors. Consequently, these better colors consistently fetch the highest prices in the market. As for the lower grades, yes, certain colors are purchased more for certain markets than for others. Rather than being a disagreement as to what is best, however, it is more a function of the buying power of the customers in that market. For example, Swiss buyers of corundum consistently purchase the better (i.e. more expensive) grades because their customers are generally more wealthy and so can afford to buy the best. In contrast, buyers from England must sell to customers in a market where the economy is depressed, and so are forced to settle for stones of lower quality. This is not to say that the people in England prefer to buy the lower grades. They just do not have enough money to purchase the best. The point here, and it is an important one, is that buyers will purchase the qualities which are most easily saleable in their home markets. Some may say that the English prefer darker rubies, while the Japanese prefer more pinkish stones. It is not that the Japanese and English buyers cannot agree upon what is best. They can. If given an unlimited amount of money to spend and if offered to a broad selection of rubies where side by side comparisons can be made, virtually all experienced buyers will choose the same stone almost every time. That is why these top quality stones fetch the highest prices in the Bangkok market.
One of Mr Sadkiel’s major objections to colored stone grading by labs was that it might bring about a stepped up demand for certain colors which are considered preferred when their availability in nature is rather rare. I fail completely to see the logic in this argument. Should we avoid telling people that Picasso and Van Gogh were great artists simply because they didn’t produce enough paintings to put one in everybody’s home? I think not.
It is interesting to note that the highest prices for the very best qualities are usually paid in the producing country itself. This is because the dealers in the country where the gem is found almost always have the most experience in buying that stone. They know the full range of qualities possible for that stone and so are better able to recognize the very top quality when it is shown to them. This may seem to contradict what I have just said about all experienced dealers agreeing on what is the best quality. The problem here is that the color memory of humans is extremely poor. Given side by side comparisons, humans are able to differentiate literally millions of colors. This ability shrinks very quickly, however, if the colors are examined one at a time. With colored gemstones, it is often not possible to make side by side comparisons—especially for the best qualities, due to their great rarity. Thus, dealers are forced to rely upon their memories when making a decision as to just where a particular stone lies within the color quality spectrum (many dealers carry with them reference stones for this purpose, because human color memory is so unreliable). Dealers in the producing countries have the most experience in judging that particular variety, and so are better able to place an individual stone in its proper rank within the spectrum. Were side-by-side comparisons are possible, dealers in the producing countries would not necessarily have such an advantage. Again, in side-by-side comparisons, my experience is that there is agreement as to which stone has the best color, even among dealers from many different countries.
The lesson to be learned here for those involved in colored stone grading is that, since side-by-side comparisons for the very rare top grades are not often possible, it will be necessary to come up with some other calibrated references (such as the GIA’s ColorMaster), as well as to consult with the most experienced dealers to determine just what constitutes the best for each individual variety. These dealers will generally not be found in the consuming countries, but instead, in the producing countries themselves.
True understanding of all colored stones is much too complex for this knowledge to be gathered into the head of a single person. Instead, I believe that increasing specialization will be required. It we want to learn and define what is best in corundum, we must go to Thailand, Burma, Sri Lanka, India, Australia and East Africa. If we want to learn what is best in emerald, we must seek out experts in Colombia, Zambia, Israel, Brazil, India, Pakistan and Afghanistan. If we want to learn what is best in Jade, we must seek out experts in Burma, China, Thailand, Hong Kong and Taiwan. These are the experts who are most qualified to judge what is best, because it is they who have the most experience in examining that particular type of stone.
Because of the tremendous difficulties involved in assimilating all of this expertise from such widely ranging sources, great mistakes in grading have occurred in the past. Many dealers are familiar with the mistakes in grading rubies made by AGL (American Gemological Laboratories) in New York during the early 1980s. Their grading of rubies was based mainly upon the hue position of the stone, in part because of the incorrect terminology used by dealers in describing such stones. As I stated earlier, dealers often describe color differences solely in terms of hue position when saturation is actually the key. Burmese rubies are said to be more red, while Thai rubies are described as being too purple. Actually, the reverse is true. The result of this lack of a properly defined color vocabulary was that AGL awarded its highest color grades to the dark Thai rubies which were the purest red in hue position (AIGS Type D, daeng dum). Burmese rubies, which have traditionally fetched the highest prices in the market (due largely to their higher saturation of color), were given lower grades because they were more purple in hue position.
Dealers quickly picked up on this discrepancy and began buying up these dark red rubies in Thailand where they were relatively cheap compared with Burmese stones, because they were graded highest in New York at AGL. Eventually AGL realized its mistake and corrected the situation, but not before considerable damage was done. To reiterate, for an effective colored stone grading language to be developed, it will require both scientific expertise as well as dealer expertise. And the dealer expertise is generally greatest at source, not just in the consuming countries.
Assimilating the knowledge from experts at the source is certainly one of the most difficult tasks facing the trade in the development of an effective colored stone grading system. There does appear, however, to be some promise for the future. Specifically what I am referring to is the establishment of gemological institutes and journals in the producing nations. The first such institute in a major producing country was the founding of AIGS in Bangkok ten years ago. Its success should provide a model for similar institutes in other producing nations.
During the nineteenth century the British were able to glean and distribute a tremendous amount of information about Asian countries and their cultures by establishing Asiatic Societies and their associated journals in a number of Asian nations. These societies provided the framework for a direct exchange of information pertaining to Asia and the rest of the world. Similarly, AIGS and this journal will also allow information about Asian gems to be distributed from the source to the rest of the world. What is needed now are similar institutes and associated publications in other major producing and trading centers. India and Sri Lanka have recently founded gemological journals which provide both fascinating and useful information about their markets. The Sauer family and others are presently working to establish an institute along the lines of AIGS in Brazil. We need institutes and journals in Burma, Colombia, China, Kenya, Tanzania, Zambia, Pakistan, Afghanistan, Nigeria, Mexico, in all the places where gems are produced. This is the only way in which the rest of the world can tap into that special knowledge and expertise that is available at the source. I am not trying to discount the importance of the work done by GIA, AGL, AGMS, DgemG, GAGB, GAA, CGA, SSEF, GAAJ, AFG, Gubelin, and others in the consuming nations. These organizations will continue to be essential in the future development of colored stone grading, particularly with regard to new and improved technologies. Today, however, very little information is being disseminated from the producing nations themselves. We must find a way to tap into the expertise at the source. Establishment of institutes and journals in the producing nations offers the most viable means of accomplishing this goal.
In summary, it is clear that much remains to be learned about colored stone grading, much work remains to be done. This will require cooperation among dealers and gemologists. Each has something to learn. Rather than looking upon one another as adversaries, let us look upon each other as colleagues, sharing in the development of something exciting, something new. Rather than looking wishfully back at the past, let us look forward to the future. Colored stone grading is here to stay, no matter how much some people might wish otherwise, because the consumers want it. And our trade exists for the consumers. They are the ones who buy our product. A great adventure awaits us. Colored stone grading can be anything that we make it. Let us work together, dealers and gemologists, to make it right.
Colored Stone Grading And The Question Of Nomenclature
(via Gemological Digest, Vol.2, No.3, 1988) William J Sersen writes:
Abstract
There is today no standardized nomenclature for color-related terms in use in the jewelry industry. It seems that every dealer and colored stone grading system designer utilizes his own version of nomenclature, often defining the same term in different ways. The net result is a lack of communication within the industry on matters pertaining to the quality grading of colored stones.
After describing some of the difficulties that can do arise from nomenclature use/misuse, the author proposes a set of terms to standardize gemstone and color descriptions. Only by adopting a standardized color nomenclature will effective color communication in the gem trade become a reality.
Introduction
Imagine for a moment that you are listening to someone describe their pet. Judging from the words they choose, you assume it is a cat they are talking about. You are later shocked to discover that their pet is in fact a dog.
Unfortunately, the current state of color communication among gemstone buyers and sellers is at times not far removed from this cat versus dog analogy. Just suppose that you see a colored stone (any colored stone will do) described on a price list as ‘fine color’. Upon actually viewing the piece, you discover that the seller’s concept of ‘fine’ corresponds roughly with your concept of ‘good’, ‘fair’, or perhaps even ‘poor’. In other words, what you thought was going to be a pedigreed cat has turned out to be a rabid dog.
As this article will demonstrate, a standardized and well-defined nomenclature of color-related terms is necessary before there can be effective color communication in the jewelry industry.
Color Terms Now Used In The Trade
Of the many colored stone grading systems that have appeared over the past ten years, some have used the same terms (tone, pleochroism, etc) to communicate different or slightly different concepts. In addition, many in the trade have coined still other terms to describe color attributes of colored stones. This creates confusion when people try to compare one system with another, or communicate with a dealer in the language of a grading system with which he is not familiar. Attempts at comparing different colored stone grading systems have never been easy; the lack of nomenclature standards has made this task even more difficult.
Before effective color communication is a reality, there must be a common language of color related terms in use both by people in the gem trade and by those involved in designing and using grading systems. That is, nomenclature must be defined in a consistent manner, without overlap, inconsistency, vagueness or redundancy in meaning. A standardized nomenclature of this sort would facilitate user comparisons of different grading systems. Users could then learn more than one system (if desired) without having to tackle yet another ‘dialect’ of color terms.
Typical examples of terms used inconsistently or redundantly are ‘overtone’, ‘pleochroism’ and ‘secondary color’. Let’s apply those terms to red spinel and ruby. One colored stone grading (AGMS:Valente, 1986) would have us think of the orangy red presence seen on certain facets in many red spinels as pleochoism, despite the fact that the pleochroism is possible only in DR stones, spinel being SR (color differences on different facets in spinel and other singly refractive gems are actually due to differences in path length or color zoning, not pleochroism). Other people might label that orangy red presence ‘absorption color (GIA: 1983) or ‘overlay color’ (Huffer: 1983), as opposed to the red ‘dominant’ color, itself sometimes called ‘primary color’ (Huffer: 1981) or ‘main color’ (Huffer: 1983; Ramsey: 1985). True color differences due to pleochroism (seen face-up on many rubies) are variously called ‘secondary color’ (Huffer: 1981), ‘pleochroism’ (AIGS and GIA) and ‘overtone’ (Ramsey: 1985), the latter suggesting the orange is superimposed over the entire crown. Overtone has also been used to designate any colors that are seen in addition to the stone’s main color (Ramsey: 1985).
Matlins and Bonanno (1987) refer to the ‘purplish cast’ (in actuality, a low saturation red) on some Thai rubies as an ‘undertone’. One American dealer recently suggested to the author that this was an incorrect use of undertone, the proper designation being ‘overcast’.
Besides referring to pleochroic color differences, secondary color has at times been associated specifically with ‘girdle facet color’ (color on facets near the girdle, viewed face up) and ‘window color’ (color on facets which show a window, viewed face up; AGMS: Valente, 1986). Varley (1980) say of secondary color that ‘the term is largely obsolete.
‘Body color’ is a prime example of a term used differently by different people. It has been thought of as a window color (Ramsey: 1985), ‘pavilion color’ (the color seen on the pavilion when a gem is placed table down; Yu: 1980) and ‘overall crown color’. Ramsey (1985) goes so far as to say that body color can be assessed by window and pavilion color, an interesting comment in that with colored stones these two colors are usually quite different.
‘Tone’, which GemDialogue has called ‘zone’ (Huffer: 1983), is another word used inconsistently. As we will see later, tone (in gems) usually describes the degree of lightness to darkness of the overall stone when viewed face up. But, this word has been used to denote ‘the amount of total color in a stone,’ a definition that misleadingly overlaps in meaning with ‘saturation’.
‘Saturation’, by the way, is called ‘intensity’ by some (AIGS, formerly) and ‘chroma’ by others, though there are those who relate the effect to ‘modifier’ (AGMS: Valente, 1986). The latter term describes degrees of desaturation, as evident by the amount of existing ‘gray’. GemDialogue has used a similar desaturation concept, known as ‘color mask’ (Huffer: 1983). Color mask, together with ‘brightness’, equates roughly in that system with the GIA’s concept of saturation (GIA: 1983). Even so, while some systems associate desaturation with gray or brown (Huffer: 1983; GIA: 1983), others associate it with gray only (AGMS: Valente, 1986), contending that brown is not a desaturant.
Are you just a little bit confused at this point? To simplify matters, I have listed but a few of the terms currently in use. The list of candidates for inconsistent/vague/redundant nomenclature usage goes on and on….
Why Do Nomenclature Problems Arise?
Dealers and gemologists together have described/created a plethora of technical terms—many of which have been borrowed or adapted from terminology in use by color scientists—for their respective methods of grading colored stones. As such terms are not always defined in the same way, defined unclearly, or constitute synonyms, it is no wonder that color communication has suffered; it is inevitable that it would suffer under such circumstances.
We can take some solace in fact that nomenclature problems are not limited to gemology and the gem trade. The development of meaningful semantic systems for describing sensory perceptions has long been a matter of concern in other fields as well, the audio and computer industries being notable examples. Let us take, for instance, the term ‘artificial intelligence’ as applied to the computer world. The question of whether it is misleading to use the word ‘intelligence’ in this context has been the object of much debate by computer people; at least one software engineer has suggested ‘artificial instinct’ as the more appropriate designation. If industries on the whole were always in agreement on the definitions and applications of technical terms, then there would be less need for organizations like ASTM (American Society For Testing And Materials), NBS (National Bureau Of Standards) or ANSI (American National Standards Institute).
Nomenclature problems in industry are further exacerbated by the tendency (often of marketing people) to believe that if the name of something is changed, it will somehow change or improve the products salability. Does the word ‘Bufferin’ sound better to you than just plain “Aspirin’? Is Tanzanite somehow more palatable than Blue Zoisite? Similarly, is ‘zone’ more appropriate than ‘tone’ for describing essentially the same thing?
Does The Answer Lie In Objective Grading?
Certain gemologists have stated that many of the present ills of colored stone grading will be removed once ‘objective (i.e.’machine’) grading is perfected. While such a goal is certainly desirable, can one really say that any color related term is objective? For that matter, does the often heard expression, ‘objective colored stone grading’, actually mean what is implies?
The Merriam Webster Dictionary (1974) defines objective as ‘…existing outside and independent of the mind….treating or dealing with facts without distortion by personal feelings or prejudices..’ Subjective is conversely defined by the same source as meaning ‘…..of, relating to, or arising within oneself or mind in contrast to what is outside…Personal…’
Now when someone makes a visual assessment of a gem’s color, is that not what a somewhat personal and hence, subjective analysis of the color? ‘Visual’ means the human eye/brain combination is a conditioning factor. Devices such as computers, image grabbers and high resolution color monitors may play the secondary role of electronically collecting, storing, sorting and ‘pigeon-holing’ color date; this does not, however, negate the eye’s role as a determinant or conditioning factor with the aid of which a grade is ultimately derived. While we certainly do look forward to the day when an electro-optical device can replace the human eye, such a day seems quite far off. That this is so is shown clearly by the fact that there is no color monitor or photographic apparatus available today which can approach the human eye/brain in its ability to resolve images. Has anyone ever seen a video image or photograph that was not immediately recognizable as such? If you have, then let us know. The fact is that the resolution ability of the eye is far greater than any device yet devised.
Can color scientists other professionals shed further light on the matter of the role of the eye? Yes they can. Many agree that people with so-called ‘normal color vision’ do not all perceive identically the full range of colors or more specifically, subtle color blends. Moreover, different ‘color normals’ vary in their aptitude to detect small color differences. The ASTM people (1987) go so far as to say that ‘persons employed in visually evaluating color differences should score near or within the ‘superior’ range of color aptitude (on Farnsworth-Munsell 100-Hue Test).
In other words, using the human eye to distinguish and assess subtle color differences does not appear to be an exercise in objectivity. We therefore submit that given the present state of colored stone grading, the phrase ‘objective colored stone grading’ should be avoided as it carries implications that are the least misleading. When instruments alone can accurately color grade gemstones with near 100% repeatability/reproducibility and without assistance from the human eye, then we can consider using the term ‘objective grading’. Unfortunately, this instrument does not yet exist. If and when it does appear, colored stone grading will become more a ‘science’ than ‘art’ and individual color terms can then assume a truly ‘objective’ status.
A Closer Look At The Main Terms
So, who is correct when assigning/defining color related terms for gem grading purposes? To help answer that question, let’s examine more closely the definitions of the major color attributes—the concepts of hue, tone and saturation—given by thirteen sources consisting of color scientists, gemological institutes, gemologists and trade journalists alike.
Hue
All sources use this term and agree on its broad meaning: ‘the position of a color on a color wheel’ (red, orange, yellow, green, blue, violet and purple, or colors intermediate between adjacent pairs of these). This ‘hue position’ includes pure spectral colors, color blends and so-called additional colors. Depending on the source, blends and additional colors are sometimes referred to as overtones, secondary colors or pleochroic colors. Some use the term pleochroism in the strict gemological sense (viz, GIA and AIGS); others (AGMS: Valente 1986) apply it more loosely. (The term ‘purity’ is often used in very different ways. Some (AIGS) use it to describe the location of a hue on a color wheel, with a pure red, for example, falling exactly midway between orange on the one side and purple on the other. Others use purity to denote the saturation of the hue; ‘pure’ red being slightly saturated red.)
Tone
Different sources use different terms to convey this concept. Six sources prefer using the word ‘tone’; four prefer ‘lightness’; three prefer ‘value’. Tone, lightness and value are at times used interchangeably.
Unfortunately, not all sources are consistent in the way they think of tone/value/lightness. The common and consistent denominator is relative darkness or lightness, with some (viz, Arem, Metheun and AIGS) describing the concept as a function of overall reflectance or transmittance (or conversely, overall absorption). Colorless (or white for opaque stones) would represent the lightness tone (zero), as none of the light striking the gem is absorbed. The greater the percentage of light absorbed, the darker the tone, with black having the darkest tone (100) as none of the light entering the gem is reflected back or transmitted through to the eye. As the term is used by AIGS, a zero tone (colorless or white) represents 100% absorption. All other colors would have tones between zero and 100.
In defining tone as the amount or quantity of total color in a stone, Huffer (1981, 1983) and Farrell & Thomas (1983) confuse the issue, as most people would associate that definition of tone with saturation than tone. Indeed, that definition of tone corresponds almost literally with Billmeyer & Saltzman’s (1981) definition of chroma (saturation).
Some associate tone/value/lightness intimately with saturation. Manson (1982) describes ‘tone’ a combination of saturation and blackness, though he elsewhere implies that tone is merely a synonym for blackness. AGMS (Valente, 1986) thinks of tone as the sum of value and ‘modifier’, the latter term meaning lack of saturation as evident by increasing presence of gray. Elsewhere, they note that tone is a combination of chroma and value. Varley (1980), in speaking of lightness compared with black or its darkest value…compared with white,’ is consistent with AGMS’(1986) definition of tone (=value + modifier).
Arem (1987) is one of the few who defines lightness/value without specific reference to chroma/saturation.
As if the issue were not complicated enough, the color scientists Overheim & Wagner (1982) observe that synonyms used for Munsell ‘value’ also include brightness, brilliance and luminosity. In the opinion of AIGS, there is a certain relationship between tone and saturation. In all cases it is correct to say that, if tone is defined in terms of overall reflectance or transmittance, increases in saturation always result in increases in tone, because higher saturation always result in increases in higher absorption. However, and it is here that confusion often exists, increases in tone do not always result in higher saturation. It is perfectly possible to have a very high tone (due to high absorption – low reflectance/transmittance), but still have a low saturation. Increasing saturation always result in increasing stone, but increasing tone does not always result in increasing saturation.
Saturation
Though the majority of sources prefer the term ‘saturation’ that term is often used interchangeably with intensity and chroma. The common denominator in most instances is the idea of color vividness. That is, how much color is present? How vivid is the color?
Some associate intensity/saturation/chroma with color purity, in the sense that the more pronounced the saturation, the more pure is the color. They think of ‘purity’ as freedom from color dilution. But, dilution by what? Here is where there is some disagreement.
Overheim & Wagner (1982) speak of dilution as freedom from black, white, gray. This is consistent with Varley (1980). However Brownlow (1983), in his article ‘Color Grading Terminology Unscrambled’, scrambles the issue somewhat when stating that a highly saturate color lacks dilution by white, black, gray and other colors. He gives as an example a yellowish green emerald, which is less saturate than a pure emerald green, saturation referring to the purity of a color. If saturation is just purity (in Brownlow’s sense of the word), then a pale yellow sapphire, with no color but yellow present, should be considered as having maximum saturation. The problem, of course, is that most people would not consider such a stone ‘vivid’ in color.
Many sources speak of saturation in a way that associates it with the absence or presence of gray, or in a few cases, gray or brown. Generally, the word gray simply refers to the amount of saturation. For example, the more gray a stone the less saturate or vivid is its color. AGMS (Valente, 1986) uses the word ‘modifier’ to describe relative degrees of color saturation in accordance with amount of gray present. Though not using the word ‘modifier’, the GIA (1983( similarly associates more ‘gray’ with the lower saturation levels.
For Metheun (1983), intensity or saturation means the density of hue present. ‘The denser the color appears, the more distinct is also the hue. A color with a distinct hue is described as being intense or saturated’. This is consistent with the AIGS definition of the term, ‘saturation’ referring to the vividness or intensity of the hue.
Analysis
With few exceptions, there is consensus on the definition and use of ‘hue’. But, there is inconsistency in how the concepts ‘tone’ and ‘saturation’ are defined. Specifically, the confusion seems to lie in defining the exact relationship of tone with saturation.
The GIA (1983b) says of tone:
‘Estimating the tone of low saturation stones can be frustrating at first. Because they tend to look grayer (or browner), it is natural to want to call them dark. Don’t confuse low saturation with dark tone. Instead, try to imagine low saturation stones as if you were looking at them on a black and white TV. Disregard the strength of hue and just ask yourself where the whole stone would fall on scale of light to dark.’
The statement: ‘don’t confuse low saturation with dark tone’ is simply not always true. Intensity/saturation/chroma—whatever you want to call it—refers to a scale of color vividness. Some ‘dirty green’ tourmalines, indicolites an many Australian blue sapphires have an overall dark appearance (= dark tone) and at the same time show color flashes of relatively low saturation. That is, the flashes are by no means strong or vivid.
Color plates or chips are useful for illustrating the concept of dark tone accompanied by low saturation. We start by selecting two plates, each containing the same amount of chromatic ink. The plates are chosen such that the first has little or no achromatic (gray) ink; the second plate is overprinted with so much gray ink as to give it a very dark (inky) appearance. The hue will appear less distinct or vivid on the second plate. The second plate is less saturate and of darker tone than the first.
It is true that three dimensional colored stones seldom display the same uniformity in color one finds with chips or plates. This is partly why one judges hue position and saturation from the flashes showing brilliancy and tone from the overall (face up) stone. With our green tourmaline, indicolite and sapphire examples, a very dark overall tone happens to correspond with relatively unsaturated brilliancy flashes. Type ‘D’ ruby exemplifies dark tone accompanying highly saturate brilliancy flashes.
Manson’s (1982) description of tone as the sum of saturation and blackness is a little confusing, in that many would think blackness and tone are the same anyway, as Manson himself seems to imply at one point in his article. So, do we infer from this that tone = saturation + tone? What exactly does that mean?
Conclusions
The research and development of colored stone grading systems is a fairly recent activity. Only the naïve would consider these systems—including that used at AIGS—as more than crude attempts at addressing the problems at hand: crude and very subjective. That so many color related terms have sprung up has a positive aspect. Marketing motives aside, new nomenclature does not arise without thought why that nomenclature is needed. This at least indicates that people are thinking of the subject. Regrettably, though, more people seem to think of the subject when colored stone prices are rising than during periods of price decline. Perhaps that is just a coincidence?
The jewelry trade must continue to research and develop colored stone grading techniques. Yet at the same time, efforts must be directed toward a standardized nomenclature so that these techniques/systems are more readily comparable and mutually translatable. Only when it becomes relatively easy to compare grading techniques will end users take the time to do so; and it is the end user who should have the final word on the matter. Standardized nomenclature will make the task all the more easy for that person.
A first step towards nomenclature standards is to get back to the basics. This means using terms that have a solid basis in color science, are familiar to the majority of gemologists, lend themselves minimally to misrepresentation and, ideally have prior acceptance by recognized color standards committees, such as ASTM.
Toward meeting these criteria, we suggest universal and consistent use of hue, lightness and saturation for describing the color appearance of gemstones, defined as follows:
Hue: The position of a color on a color wheel (red, orange, yellow, green, blue, violet, and purple, or colors intermediate between adjacent pairs of these).
Lightness: The relative darkness or lightness of the hue as a function of overall reflectance or transmittance (or conversely, overall absorption).
Saturation: The vividness or intensity of the hue.
All three terms are included in ASTM’s E-284 Standard Definitions of Terms Relating to Appearance of Materials. The majority of colored stone grading system designers and color scientists use hue, and we are generally consistent when defining it. Most of these same people prefer the term saturation to express the concept of color vividness. Lightness, it is true, is cited by only two of our gemological sources (Arem and Brownlow). But, the term is used extensively by color scientists, and does not lend itself to readily to the kind of misinterpretation one finds with tone, lightness being an almost self-explained term.
We propose that use be discouraged of terms like modifier, zone, overtone and body color. The first two are little more than synonyms for existing terms (saturation and lightness, respectively); the last two have always meant far too many things to too many people. None of the four have any widespread use in color science or are recognized by ASTM.
The term pleochroism or pleochroic color (s) seems preferable to other color descriptive designations like secondary color (which could refer to just about anything) to describe that color phenomenon. However, in keeping with standard gemological usage, pleochroism should be applied only to doubly refractive stones which do display visible pleochroism in the face-up position, as confirmed by examination through a calcite (not Polaroid) dichroscope.
It is the author’s firm belief that if progress is to be made in the field of colored stone grading, the gem trade must first take steps to standardize the terminology used in describing the color appearance of gemstones. Without a uniformly defined and applied color nomenclature, effective color communication will remain but a pipe dream.
Abstract
There is today no standardized nomenclature for color-related terms in use in the jewelry industry. It seems that every dealer and colored stone grading system designer utilizes his own version of nomenclature, often defining the same term in different ways. The net result is a lack of communication within the industry on matters pertaining to the quality grading of colored stones.
After describing some of the difficulties that can do arise from nomenclature use/misuse, the author proposes a set of terms to standardize gemstone and color descriptions. Only by adopting a standardized color nomenclature will effective color communication in the gem trade become a reality.
Introduction
Imagine for a moment that you are listening to someone describe their pet. Judging from the words they choose, you assume it is a cat they are talking about. You are later shocked to discover that their pet is in fact a dog.
Unfortunately, the current state of color communication among gemstone buyers and sellers is at times not far removed from this cat versus dog analogy. Just suppose that you see a colored stone (any colored stone will do) described on a price list as ‘fine color’. Upon actually viewing the piece, you discover that the seller’s concept of ‘fine’ corresponds roughly with your concept of ‘good’, ‘fair’, or perhaps even ‘poor’. In other words, what you thought was going to be a pedigreed cat has turned out to be a rabid dog.
As this article will demonstrate, a standardized and well-defined nomenclature of color-related terms is necessary before there can be effective color communication in the jewelry industry.
Color Terms Now Used In The Trade
Of the many colored stone grading systems that have appeared over the past ten years, some have used the same terms (tone, pleochroism, etc) to communicate different or slightly different concepts. In addition, many in the trade have coined still other terms to describe color attributes of colored stones. This creates confusion when people try to compare one system with another, or communicate with a dealer in the language of a grading system with which he is not familiar. Attempts at comparing different colored stone grading systems have never been easy; the lack of nomenclature standards has made this task even more difficult.
Before effective color communication is a reality, there must be a common language of color related terms in use both by people in the gem trade and by those involved in designing and using grading systems. That is, nomenclature must be defined in a consistent manner, without overlap, inconsistency, vagueness or redundancy in meaning. A standardized nomenclature of this sort would facilitate user comparisons of different grading systems. Users could then learn more than one system (if desired) without having to tackle yet another ‘dialect’ of color terms.
Typical examples of terms used inconsistently or redundantly are ‘overtone’, ‘pleochroism’ and ‘secondary color’. Let’s apply those terms to red spinel and ruby. One colored stone grading (AGMS:Valente, 1986) would have us think of the orangy red presence seen on certain facets in many red spinels as pleochoism, despite the fact that the pleochroism is possible only in DR stones, spinel being SR (color differences on different facets in spinel and other singly refractive gems are actually due to differences in path length or color zoning, not pleochroism). Other people might label that orangy red presence ‘absorption color (GIA: 1983) or ‘overlay color’ (Huffer: 1983), as opposed to the red ‘dominant’ color, itself sometimes called ‘primary color’ (Huffer: 1981) or ‘main color’ (Huffer: 1983; Ramsey: 1985). True color differences due to pleochroism (seen face-up on many rubies) are variously called ‘secondary color’ (Huffer: 1981), ‘pleochroism’ (AIGS and GIA) and ‘overtone’ (Ramsey: 1985), the latter suggesting the orange is superimposed over the entire crown. Overtone has also been used to designate any colors that are seen in addition to the stone’s main color (Ramsey: 1985).
Matlins and Bonanno (1987) refer to the ‘purplish cast’ (in actuality, a low saturation red) on some Thai rubies as an ‘undertone’. One American dealer recently suggested to the author that this was an incorrect use of undertone, the proper designation being ‘overcast’.
Besides referring to pleochroic color differences, secondary color has at times been associated specifically with ‘girdle facet color’ (color on facets near the girdle, viewed face up) and ‘window color’ (color on facets which show a window, viewed face up; AGMS: Valente, 1986). Varley (1980) say of secondary color that ‘the term is largely obsolete.
‘Body color’ is a prime example of a term used differently by different people. It has been thought of as a window color (Ramsey: 1985), ‘pavilion color’ (the color seen on the pavilion when a gem is placed table down; Yu: 1980) and ‘overall crown color’. Ramsey (1985) goes so far as to say that body color can be assessed by window and pavilion color, an interesting comment in that with colored stones these two colors are usually quite different.
‘Tone’, which GemDialogue has called ‘zone’ (Huffer: 1983), is another word used inconsistently. As we will see later, tone (in gems) usually describes the degree of lightness to darkness of the overall stone when viewed face up. But, this word has been used to denote ‘the amount of total color in a stone,’ a definition that misleadingly overlaps in meaning with ‘saturation’.
‘Saturation’, by the way, is called ‘intensity’ by some (AIGS, formerly) and ‘chroma’ by others, though there are those who relate the effect to ‘modifier’ (AGMS: Valente, 1986). The latter term describes degrees of desaturation, as evident by the amount of existing ‘gray’. GemDialogue has used a similar desaturation concept, known as ‘color mask’ (Huffer: 1983). Color mask, together with ‘brightness’, equates roughly in that system with the GIA’s concept of saturation (GIA: 1983). Even so, while some systems associate desaturation with gray or brown (Huffer: 1983; GIA: 1983), others associate it with gray only (AGMS: Valente, 1986), contending that brown is not a desaturant.
Are you just a little bit confused at this point? To simplify matters, I have listed but a few of the terms currently in use. The list of candidates for inconsistent/vague/redundant nomenclature usage goes on and on….
Why Do Nomenclature Problems Arise?
Dealers and gemologists together have described/created a plethora of technical terms—many of which have been borrowed or adapted from terminology in use by color scientists—for their respective methods of grading colored stones. As such terms are not always defined in the same way, defined unclearly, or constitute synonyms, it is no wonder that color communication has suffered; it is inevitable that it would suffer under such circumstances.
We can take some solace in fact that nomenclature problems are not limited to gemology and the gem trade. The development of meaningful semantic systems for describing sensory perceptions has long been a matter of concern in other fields as well, the audio and computer industries being notable examples. Let us take, for instance, the term ‘artificial intelligence’ as applied to the computer world. The question of whether it is misleading to use the word ‘intelligence’ in this context has been the object of much debate by computer people; at least one software engineer has suggested ‘artificial instinct’ as the more appropriate designation. If industries on the whole were always in agreement on the definitions and applications of technical terms, then there would be less need for organizations like ASTM (American Society For Testing And Materials), NBS (National Bureau Of Standards) or ANSI (American National Standards Institute).
Nomenclature problems in industry are further exacerbated by the tendency (often of marketing people) to believe that if the name of something is changed, it will somehow change or improve the products salability. Does the word ‘Bufferin’ sound better to you than just plain “Aspirin’? Is Tanzanite somehow more palatable than Blue Zoisite? Similarly, is ‘zone’ more appropriate than ‘tone’ for describing essentially the same thing?
Does The Answer Lie In Objective Grading?
Certain gemologists have stated that many of the present ills of colored stone grading will be removed once ‘objective (i.e.’machine’) grading is perfected. While such a goal is certainly desirable, can one really say that any color related term is objective? For that matter, does the often heard expression, ‘objective colored stone grading’, actually mean what is implies?
The Merriam Webster Dictionary (1974) defines objective as ‘…existing outside and independent of the mind….treating or dealing with facts without distortion by personal feelings or prejudices..’ Subjective is conversely defined by the same source as meaning ‘…..of, relating to, or arising within oneself or mind in contrast to what is outside…Personal…’
Now when someone makes a visual assessment of a gem’s color, is that not what a somewhat personal and hence, subjective analysis of the color? ‘Visual’ means the human eye/brain combination is a conditioning factor. Devices such as computers, image grabbers and high resolution color monitors may play the secondary role of electronically collecting, storing, sorting and ‘pigeon-holing’ color date; this does not, however, negate the eye’s role as a determinant or conditioning factor with the aid of which a grade is ultimately derived. While we certainly do look forward to the day when an electro-optical device can replace the human eye, such a day seems quite far off. That this is so is shown clearly by the fact that there is no color monitor or photographic apparatus available today which can approach the human eye/brain in its ability to resolve images. Has anyone ever seen a video image or photograph that was not immediately recognizable as such? If you have, then let us know. The fact is that the resolution ability of the eye is far greater than any device yet devised.
Can color scientists other professionals shed further light on the matter of the role of the eye? Yes they can. Many agree that people with so-called ‘normal color vision’ do not all perceive identically the full range of colors or more specifically, subtle color blends. Moreover, different ‘color normals’ vary in their aptitude to detect small color differences. The ASTM people (1987) go so far as to say that ‘persons employed in visually evaluating color differences should score near or within the ‘superior’ range of color aptitude (on Farnsworth-Munsell 100-Hue Test).
In other words, using the human eye to distinguish and assess subtle color differences does not appear to be an exercise in objectivity. We therefore submit that given the present state of colored stone grading, the phrase ‘objective colored stone grading’ should be avoided as it carries implications that are the least misleading. When instruments alone can accurately color grade gemstones with near 100% repeatability/reproducibility and without assistance from the human eye, then we can consider using the term ‘objective grading’. Unfortunately, this instrument does not yet exist. If and when it does appear, colored stone grading will become more a ‘science’ than ‘art’ and individual color terms can then assume a truly ‘objective’ status.
A Closer Look At The Main Terms
So, who is correct when assigning/defining color related terms for gem grading purposes? To help answer that question, let’s examine more closely the definitions of the major color attributes—the concepts of hue, tone and saturation—given by thirteen sources consisting of color scientists, gemological institutes, gemologists and trade journalists alike.
Hue
All sources use this term and agree on its broad meaning: ‘the position of a color on a color wheel’ (red, orange, yellow, green, blue, violet and purple, or colors intermediate between adjacent pairs of these). This ‘hue position’ includes pure spectral colors, color blends and so-called additional colors. Depending on the source, blends and additional colors are sometimes referred to as overtones, secondary colors or pleochroic colors. Some use the term pleochroism in the strict gemological sense (viz, GIA and AIGS); others (AGMS: Valente 1986) apply it more loosely. (The term ‘purity’ is often used in very different ways. Some (AIGS) use it to describe the location of a hue on a color wheel, with a pure red, for example, falling exactly midway between orange on the one side and purple on the other. Others use purity to denote the saturation of the hue; ‘pure’ red being slightly saturated red.)
Tone
Different sources use different terms to convey this concept. Six sources prefer using the word ‘tone’; four prefer ‘lightness’; three prefer ‘value’. Tone, lightness and value are at times used interchangeably.
Unfortunately, not all sources are consistent in the way they think of tone/value/lightness. The common and consistent denominator is relative darkness or lightness, with some (viz, Arem, Metheun and AIGS) describing the concept as a function of overall reflectance or transmittance (or conversely, overall absorption). Colorless (or white for opaque stones) would represent the lightness tone (zero), as none of the light striking the gem is absorbed. The greater the percentage of light absorbed, the darker the tone, with black having the darkest tone (100) as none of the light entering the gem is reflected back or transmitted through to the eye. As the term is used by AIGS, a zero tone (colorless or white) represents 100% absorption. All other colors would have tones between zero and 100.
In defining tone as the amount or quantity of total color in a stone, Huffer (1981, 1983) and Farrell & Thomas (1983) confuse the issue, as most people would associate that definition of tone with saturation than tone. Indeed, that definition of tone corresponds almost literally with Billmeyer & Saltzman’s (1981) definition of chroma (saturation).
Some associate tone/value/lightness intimately with saturation. Manson (1982) describes ‘tone’ a combination of saturation and blackness, though he elsewhere implies that tone is merely a synonym for blackness. AGMS (Valente, 1986) thinks of tone as the sum of value and ‘modifier’, the latter term meaning lack of saturation as evident by increasing presence of gray. Elsewhere, they note that tone is a combination of chroma and value. Varley (1980), in speaking of lightness compared with black or its darkest value…compared with white,’ is consistent with AGMS’(1986) definition of tone (=value + modifier).
Arem (1987) is one of the few who defines lightness/value without specific reference to chroma/saturation.
As if the issue were not complicated enough, the color scientists Overheim & Wagner (1982) observe that synonyms used for Munsell ‘value’ also include brightness, brilliance and luminosity. In the opinion of AIGS, there is a certain relationship between tone and saturation. In all cases it is correct to say that, if tone is defined in terms of overall reflectance or transmittance, increases in saturation always result in increases in tone, because higher saturation always result in increases in higher absorption. However, and it is here that confusion often exists, increases in tone do not always result in higher saturation. It is perfectly possible to have a very high tone (due to high absorption – low reflectance/transmittance), but still have a low saturation. Increasing saturation always result in increasing stone, but increasing tone does not always result in increasing saturation.
Saturation
Though the majority of sources prefer the term ‘saturation’ that term is often used interchangeably with intensity and chroma. The common denominator in most instances is the idea of color vividness. That is, how much color is present? How vivid is the color?
Some associate intensity/saturation/chroma with color purity, in the sense that the more pronounced the saturation, the more pure is the color. They think of ‘purity’ as freedom from color dilution. But, dilution by what? Here is where there is some disagreement.
Overheim & Wagner (1982) speak of dilution as freedom from black, white, gray. This is consistent with Varley (1980). However Brownlow (1983), in his article ‘Color Grading Terminology Unscrambled’, scrambles the issue somewhat when stating that a highly saturate color lacks dilution by white, black, gray and other colors. He gives as an example a yellowish green emerald, which is less saturate than a pure emerald green, saturation referring to the purity of a color. If saturation is just purity (in Brownlow’s sense of the word), then a pale yellow sapphire, with no color but yellow present, should be considered as having maximum saturation. The problem, of course, is that most people would not consider such a stone ‘vivid’ in color.
Many sources speak of saturation in a way that associates it with the absence or presence of gray, or in a few cases, gray or brown. Generally, the word gray simply refers to the amount of saturation. For example, the more gray a stone the less saturate or vivid is its color. AGMS (Valente, 1986) uses the word ‘modifier’ to describe relative degrees of color saturation in accordance with amount of gray present. Though not using the word ‘modifier’, the GIA (1983( similarly associates more ‘gray’ with the lower saturation levels.
For Metheun (1983), intensity or saturation means the density of hue present. ‘The denser the color appears, the more distinct is also the hue. A color with a distinct hue is described as being intense or saturated’. This is consistent with the AIGS definition of the term, ‘saturation’ referring to the vividness or intensity of the hue.
Analysis
With few exceptions, there is consensus on the definition and use of ‘hue’. But, there is inconsistency in how the concepts ‘tone’ and ‘saturation’ are defined. Specifically, the confusion seems to lie in defining the exact relationship of tone with saturation.
The GIA (1983b) says of tone:
‘Estimating the tone of low saturation stones can be frustrating at first. Because they tend to look grayer (or browner), it is natural to want to call them dark. Don’t confuse low saturation with dark tone. Instead, try to imagine low saturation stones as if you were looking at them on a black and white TV. Disregard the strength of hue and just ask yourself where the whole stone would fall on scale of light to dark.’
The statement: ‘don’t confuse low saturation with dark tone’ is simply not always true. Intensity/saturation/chroma—whatever you want to call it—refers to a scale of color vividness. Some ‘dirty green’ tourmalines, indicolites an many Australian blue sapphires have an overall dark appearance (= dark tone) and at the same time show color flashes of relatively low saturation. That is, the flashes are by no means strong or vivid.
Color plates or chips are useful for illustrating the concept of dark tone accompanied by low saturation. We start by selecting two plates, each containing the same amount of chromatic ink. The plates are chosen such that the first has little or no achromatic (gray) ink; the second plate is overprinted with so much gray ink as to give it a very dark (inky) appearance. The hue will appear less distinct or vivid on the second plate. The second plate is less saturate and of darker tone than the first.
It is true that three dimensional colored stones seldom display the same uniformity in color one finds with chips or plates. This is partly why one judges hue position and saturation from the flashes showing brilliancy and tone from the overall (face up) stone. With our green tourmaline, indicolite and sapphire examples, a very dark overall tone happens to correspond with relatively unsaturated brilliancy flashes. Type ‘D’ ruby exemplifies dark tone accompanying highly saturate brilliancy flashes.
Manson’s (1982) description of tone as the sum of saturation and blackness is a little confusing, in that many would think blackness and tone are the same anyway, as Manson himself seems to imply at one point in his article. So, do we infer from this that tone = saturation + tone? What exactly does that mean?
Conclusions
The research and development of colored stone grading systems is a fairly recent activity. Only the naïve would consider these systems—including that used at AIGS—as more than crude attempts at addressing the problems at hand: crude and very subjective. That so many color related terms have sprung up has a positive aspect. Marketing motives aside, new nomenclature does not arise without thought why that nomenclature is needed. This at least indicates that people are thinking of the subject. Regrettably, though, more people seem to think of the subject when colored stone prices are rising than during periods of price decline. Perhaps that is just a coincidence?
The jewelry trade must continue to research and develop colored stone grading techniques. Yet at the same time, efforts must be directed toward a standardized nomenclature so that these techniques/systems are more readily comparable and mutually translatable. Only when it becomes relatively easy to compare grading techniques will end users take the time to do so; and it is the end user who should have the final word on the matter. Standardized nomenclature will make the task all the more easy for that person.
A first step towards nomenclature standards is to get back to the basics. This means using terms that have a solid basis in color science, are familiar to the majority of gemologists, lend themselves minimally to misrepresentation and, ideally have prior acceptance by recognized color standards committees, such as ASTM.
Toward meeting these criteria, we suggest universal and consistent use of hue, lightness and saturation for describing the color appearance of gemstones, defined as follows:
Hue: The position of a color on a color wheel (red, orange, yellow, green, blue, violet, and purple, or colors intermediate between adjacent pairs of these).
Lightness: The relative darkness or lightness of the hue as a function of overall reflectance or transmittance (or conversely, overall absorption).
Saturation: The vividness or intensity of the hue.
All three terms are included in ASTM’s E-284 Standard Definitions of Terms Relating to Appearance of Materials. The majority of colored stone grading system designers and color scientists use hue, and we are generally consistent when defining it. Most of these same people prefer the term saturation to express the concept of color vividness. Lightness, it is true, is cited by only two of our gemological sources (Arem and Brownlow). But, the term is used extensively by color scientists, and does not lend itself to readily to the kind of misinterpretation one finds with tone, lightness being an almost self-explained term.
We propose that use be discouraged of terms like modifier, zone, overtone and body color. The first two are little more than synonyms for existing terms (saturation and lightness, respectively); the last two have always meant far too many things to too many people. None of the four have any widespread use in color science or are recognized by ASTM.
The term pleochroism or pleochroic color (s) seems preferable to other color descriptive designations like secondary color (which could refer to just about anything) to describe that color phenomenon. However, in keeping with standard gemological usage, pleochroism should be applied only to doubly refractive stones which do display visible pleochroism in the face-up position, as confirmed by examination through a calcite (not Polaroid) dichroscope.
It is the author’s firm belief that if progress is to be made in the field of colored stone grading, the gem trade must first take steps to standardize the terminology used in describing the color appearance of gemstones. Without a uniformly defined and applied color nomenclature, effective color communication will remain but a pipe dream.
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