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Thursday, May 17, 2007

Colorado Rhodochrosite

The Sweet Home mine in Colarado's Alma mining district has been known since 1872 for silver, but more recently the mine has become famous for producing top quality rhodochrosite crystals. The best qualities are well-formed, translucent to transparent rhombohedrons with intense orange red color. The colors are stunning red like some of the top quality rubies.

Rhodochrosite is soft and has perfect cleavage in three directions so faceting the stone is difficult. The cut yield can range between 5% and 20% depending on the size and shape of the rough and the experience of the cutter. The smaller sizes may be calibrated in 0.5mm increments as oval, round, princess, cushion, emerald and trilliants. Cabochons both calibrated and free sizes can also be polished based on the quality of the rough. Cabochons displaying chatoyancy with four rayed stars have also been found. It is believed that most faceted stones are untreated, while some of the cabochons may be stabilized during the cutting process.

The cut rhodochrosite is being sold by Mr Van Wagoner, Beija-flor Gems, Haiku, Hawaii. They expect the stocks to last for two or three years, after which few stones will be available in the market.

Australia’s Quota System For Cultured Pearls

I wish the colored stone industry had similar quota systems to protect natural environment + long term sustainability plan.

(via Arafura Pearls Holdings Ltd (2006) Prospectus/ The Australian Gemmologist, 2007, Vol.23, No.2, April-June 2007) Australian Gemmologist writes:

Unlike the rest of the world, the Australian pearl culturing industry is highly regulated through the use of a government controlled ‘oyster’ quota system. Each producer must hold a pearl license from the relevant state government body. Presently quotas are set for both wild and hatchery bred Pinctada maxima.

This quota system limits the number of shell that can be seeded and can be put into cultivation each licensing year. The sole purpose of this rigidly enforced quota system is to protect naturally occurring stocks of P. maxima, allow their natural regeneration, and so maintain the long term sustainability of the Australian South Sea pearl industry and its markets.

Presently the annual quota of shell for all licensed produces is 1,432,000 shell of specified size (120mm minimum diameter).

Wild oyster quota: 572,000 (WA); 120,000 (NT); Total: 692,000
Hatchery quota: 350,000 (WA); 300,000 (NT); Total: 650,000
Total oyster quota: 922,000 (WA); 420,000 (NT); Total: 1.342,000

The oyster quotas in the Northern Territory and Western Australia are closely held by a small number of producers. The three largest quota holders in Australia are the Paspaley Group, the Kailis Group, and Arafura Pearls who have access to approximately 75% of the available quota either directly or indirectly. The remaining quota is spread amongst several other pearl farmers.

An independent review of the Western Australian Pearling Act 1990 was completed in 2000 within the framework of the National Competition Policy. This review confirmed that the existing regulations and restrictions associated with wild stock oysters were justified. The State and Territory governments are currently completing a five year review of their hatchery policies to determine any update in hatchery quota regulation.

Pearling is Australia’s second largest aquacultural activity by gross value of production. Subject to currency and price movements, the Australian cultured pearl industry produces approximately $A180 - $220 million pearls in wholesale value each year; of which Western Australia contributes approximately 80% and the Northern Territory 20%, Queensland production is minimal. By volume, Australia produces approximately 2.5 – 3 tonnes of South Sea Pearls per annum.

A Question Of Origin

2007: I think John Koivula was right. The laboratories have no need for origin, and in some cases there is no way of knowing where the stones came from.

(via Gemological Digest, Vol.3, No.1, 1990) John Koivula writes:

With regard to your article, “A Question of Origin,” I agree with your basic premise that where determining country of origin in a gem is concerned, there is some truth in the saying ignorance is bliss. The more knowledge one gains on this subject, the more complex the problem of geographical origin becomes. While an experienced, knowledgeable inclusion expert can identify country of origin for some stones, in most cases it is impossible to determine the precise country of origin. The inclusion identification work that is done by a few colleagues and myself at GIA is done as a scientific endeavor to expand our knowledge of gems—not to prepare country of origin reports.

Your statement that ‘consumer could then be told honestly that these (origin reports) are intended for collectors and researchers’ is part incorrect, because most researchers have no need for origin reports of the type produced by the various gemological laboratories that issue them. Most inclusion researchers study the stones themselves and draw information from the various professional gemological and other earth science publications. In the 25 years that I have done research in this field, I have never found a need for an origin report.

With regard to your comments on there being more than one sapphire mining area in the State of Montana, please be assured that when Dr Gubelin and I discuss inclusions in sapphires from Yogo Gulch in the Photoatlas, we are most definitely referring to stones from that specific locality. Also, in your discussion of Kashmir sapphires you state: “Since the mine is (and has been for many years) off-limits to foreigners, the question arises as to where gemologists got the study samples.” You fail to mention or reference, however, a relatively recent major article on the Kashmir deposit in which the authors obtained their information and samples first-hand at the mining area (D. Atkinson and R. Kothawala, “Kashmir Sapphire,” Gems & Gemology, Vol.19, No.2, 1983, pp 64-76). For some interested in scientific research on Kashmir sapphires, a 1983 article would seem to be at least as valuable as one published in 1890—especially considering the technological advances that have occurred in the interim. I am sure the gemological community is also looking forward to the results of your research on the 1 kg (5000 carats) of known Kashmir sapphire rough you had the good fortune to obtain.

Inclusions As Criteria In Gemstone Origin Reports

2007: The amazing thing is despite the limitations, the trade still insists for origin certification and a few gem testing laboratories are more than happy to provide their services at a cost.

(via Gemological Digest, No.3, No.1, 1990) Edwin Roedder writes:

Richard W Hughes has asked for my comments on the question of the use of gemstone origin reports and in particular on his paper on that subject in this same issue. As a mineralogist-geochemist who has only seen the fringes of the field of gemology over the years, it is not appropriate for me to discuss the uses being made of origin reports in the gem trade. I can only say that Mr Hughes paper seems to present a very coherent, well-documented and cogent review of the subject. Although I have read many scientific papers dealing with the inclusions in gems and the possibility of their use in determining origin, I have never seen an actual origin report, and hence my only comments deal the validity of the inclusions criteria that might be used in issuing any such report. These comments are quite apart from the difficulties mentioned by Mr Hughes of obtaining material of verifiable origin on which to establish such criteria.

I will discuss two aspects: first, the effects of the inherent variation in the inclusion population in samples from a given locality, and second, the general similarity of the inclusion populations in samples from many different localities.

Variation of the inclusion parameters within samples from a given locality
Many different kinds of inclusions, both fluid and solid, can be trapped in a given mineral from a given locality. The reasons for this wide range lie in the basic nature of the origin of inclusions. Primary inclusions formed during the growth of the host crystal, can trap any solid, liquid, or vapor phases that happen to be present at the time of growth. The much more common secondary inclusions are trapped as a result of healing of fractures in the host crystal that form at some later time; this later time may be immediately after completion of the growth of the host crystal, or as much as billions of years later.

Although I have studied a number of gem minerals, the bulk of my inclusion work has been on non-gem materials, but I am certain that the principals involved in the two types of materials are identical; the only real difference is in the rarity of gem minerals, and in the necessarily low abundance of inclusions in high quality stones. When I study the inclusions in many samples of a given mineral from a given locality (personally collected so there is no ambiguity as to sample origin), I usually find a large range in inclusion types, habits, and compositions in the different samples. The primary solid inclusions represent the trapping of those other solid phases that just happened to be present at the time of growth and which were enclosed rather than pushed aside by the growing crystal. If different solid phases were present in different part of the deposit, the solid inclusions that are trapped will differ similarly. Even the fluid that is trapped in primary inclusions can show gross differences in composition between the core and rim of a single host crystal, if the conditions have changed during that growth. Since some of the larger crystals in metamorphic rocks have recently been shown to have grown at rates in the range of only a millimeter in a million years, it would not be surprising to find that the composition of the fluids bathing the crystal had changed during its growth.

Secondary fluid inclusions (i.e most of the inclusions making up the feathers, etc in gems), represent one or more periods of fracturing and rehealing of the host crystal. It is very common to find that such fracturing has occurred at several different times, perhaps millions of years apart, and in the presence of very different fluids. So two different feathers in a single crystal may contain very different fluids.

Since such wide variations in the inclusions in different crystal or parts of a crystal from a single locality are so common, it may be difficult or even impossible to set up inclusion criteria that would permit a valid origin report to be written for a single sample of the host mineral from that locality. Various specific inclusion parameters seen in the single sample may match features seen commonly in other crystals from that same locality, but the wide range of possible parameter values, and the all-too-common atypical inclusions diminish the degree of confidence in any assignment of the sample to that locality. Although my work involves learning about the inclusions in samples from known localities, I would find it exceedingly difficult to have to work in reverse, as the gemologist must, and identify the locality of origin by the study of inclusions in a given sample. If presented with a single sample from one of the many localities I have studied, I might be able to venture an educated guess as to one (or more, as detailed below) possible localities, and in most cases I could say with some confidence that certain other localities were impossible, but I could not go beyond that. Perhaps in the future, when far more inclusion parameters can be determined with increased precision, this basic uncertainity might be reduced. Thus non-destructive chemical (and isotopic) analyses of the minor and trace elements in the fluids of inclusions might provide fingerprints that will greatly reduce the ambiguity in the assignment of origin, but will never eliminate.

Similarity of inclusion populations in samples from different localities
Gemstones, just as other natural crystals, have crystallized in a variety of geological environments, but even so, there is a relatively limited range for any given gem. Thus most gem quality corundums have formed in only a very few limited types of environment, such as certain slowly cooled igneous and metamorphic rocks. As a result, the overall range in composition of their inclusions, both solid and liquid is limited. A relatively rare phase as a solid inclusion may be a valuable but not necessarily unique indicator, e.g. the uranium pyrochlore referred to in Pailin sapphires. But many solid inclusions are of common minerals that might be expected in many localities, particularly in localities that are already similar geologically in virtue of the fact that a given gemstone is found in each. (On the other hand, certain solid inclusions can effectively exclude specific geologic environments. Thus fine fibrous amphibole inclusions are not expected in stones from a magmatic or high temperature metamorphic environment.)

Similarly, liquid inclusions in most minerals normally contain water + salt + CO2 major components. The amounts of the latter two may vary widely. For many years it was generally accepted that emeralds containing highly saline inclusions (i.e a saturated water solution plus a daughter crystal of NaCl) came from Colombian emeralds, but since then similar inclusions have been described in emeralds from other localities. CO2 is a major component in the fluid inclusions in many rock types that bear gem corundum and hence is not definitive of any specific locality.

If all the above caveats seem unduly pessimistic a to the significance of origin reports, please note that I have described only one of the many parameters that may be involved in judging the origin of a stone; I am not qualified to discuss color and its distribution and possible modification, fluorescence, density, refractive index, etc.

In closing, let me add one additional caveat. Origin reports must distinguish between synthetic and natural stones, as this is far greater importance in commerce than the difference between different localities, large as these are. In the past, the inclusions in gems have provided reliable criteria for differentiating. Synthetic stones generally had types of inclusions that were uncharacteristic of those from nature, and did not contain those that were characteristic of the natural stones. These differences are caused by the use of entirely different growth processes and conditions in the laboratory than were used in nature. Thus the manufacture of large corundum crystals in various colors by flame fusion provides high quality material for pennies per carat.

But it should be noted that the huge differences in value compared with natural stones provides a great incentive to eliminate these recognizable differences in the final product. Once careful study shows the nature of the inclusions present in (and believed to be characteristic of) the natural stones, it is highly likely that attempts will be made to grow synthetic stones by processes such that the inclusions will also appear natural. Presently available laboratory equipment can duplicate the pressure, temperature, and chemical environment under which any gem has formed in nature. This has been done with emeralds, which have been grown synthetically with strongly saline inclusions, and I have no reason to doubt that other natural appearing gems will be similarly produced and sold, if they have not been already.

Wednesday, May 16, 2007

Opal From Piaui, Brazil

Piaui State (Brazil) is well-known to produce a variety of opals. Some rough and cut play of color opals are of high quality; cat's eye specimens are also available. Pedro II (or Pedro Segundo) is an important locality for play of color opals in the state. There are many new operational mines in the area. More opal production is anticipated as additional mines are reworked in part due to State government's assistance in promoting awareness of Piaui's opals.

East And West: The Ancient Gem Trade Between India and Rome

2007: Here is a fascinating story on gem trade and practices of the ancient world. Even today the concept remains pretty much the same; instead we use new jargons. It's educational and entertaining.

(via Gemological Digest, Vol.3, No.1, 1990) Peter Francis, Jr writes:

Abstract
The Roman Empire was among the best customers of the ancient world. From outside the Empire she sought items of luxury, especially precious gems. India was pleased to supply the insatiable appetite of the Roman elite. In turn, Rome paid mostly in gold coin, and supplied India with only one desired luxury, coral. The ancient gem trade was characterized by much mystery surrounding the sources of jewels, at least some of it purposeful smoke screen to ward off competition. In addition, there was general ignorance about the nature of gems such as pearls and coral. Even more important than the commerce in what we call precious stones was that in semi precious stones. Recent archaeological work has helped reveal some of the facts of this once thriving Indian industry.

Introduction
To the ancient Romans, the East, especially India, was the depository of all wealth. The Indians not only sold her mineral treasures to Rome, but were leaders in developing technologies that allowed them to be exploited.

Just over 2000 years ago the sea-faring Arabs taught Roman sailors an important secret: how to sail through the Erythraean or Red Sea, which then included the whole of the western Indian Ocean. The secret involved understanding the predominant wind patters by which ships could sail from west to east for a few months and then back from east to west during the other half of the year. This took advantage of the famous trade winds.

In those days Rome was the greatest power in the West. Aristrocrats were only politically ascendant, but also fabulously wealthy. They demanded objects that could prove their wealth beyond doubt, especially those for ostentatious display. For a very long time the best way to show off wealth has been to wear jewelry. Precious stones set in precious metals and worn by the precious few are a principal means of demonstrating that one has arrived and is rich, whether nouveau or otherwise.

This is why the discovery of a simple sea route to the East was so important to the Romans. Above all, the East meant wealth, treasure, gems and jewels beyond imagination; it was considered the depository of all valuable goods.

There were two mighty empires in the East: China and India. China was a wealthy land but also an impenetrable mystery. Though trade trickled across mountains and deserts between China and Rome, sea routes were long and dangerous and hardly ever used over such a vast distance. The Mediterranean world and China were isolated for centuries, save for the Silk Route, which was periodically closed by Central Asian bandits whenever control was weak in the Middle Kingdom.

But India was different story. A land widely renowned for its treasure, India had long traded luxury products to the western world. Millenia before Rome was built, carnelian and lapis lazuli were sold by the Indus Valley Civilization to the city states of Mesopotamia. King Solomon of Israel around 1000 B.C sent ships to Ophir to fetch gold and silver, precious stones and ivory. Though scholars disagree on exactly where Ophir was, the evidence points to India. Thus, India’s reputation as a land of riches predates the Roman Empire by centuries. By the time the Romans were masters of the western world they were anxious to seek her wealth and bring it home.

The treasures of India and Western myths
Fabulous treasures often breed fabulous ideas. In the pre-scientific ages nearly any account told by travelers and traders was accepted at face value. Miners and sellers of precious minerals did not want to reveal their sources, so they fabricated stories about how they found them. As these tales were passed around, they acquired the air of truth. The days of systematic exploration were still far off. Stories which only make us smile today were once widely believed. They explained the sources of precious materials in an entertaining and satisfying way, often emphasizing the dangers involved in securing the earth’s riches, the better to ward off would be poachers and thereby inflate prices.

The Romans believed that Indian gold was dug by ants. India has long been a gold importer, but also produced gold of its own. The gold mines near Hutti in southern India go back to this age, and old shafts go down to 250 feet (80 meters). The mines near Kolar, also in southern India, may not be that old, but have been worked so long and are so deep (up to 650 feet or 200 meters) that today they are being used for an experiment by physicists to determine whether protons, one of the constituents of atoms, every decay. These experiments must be carried out in deep mines to shield the sensitive equipment from cosmic rays, and the abandoned Kolar gold mines are perfect for this purpose.

But the Romans knew nothing about nuclear physics; they believed that insects mined gold in India. The historian Herodotus said that ants bigger than foxes brought up gold nuggets the size of walnuts while building their hill. Men had to get the gold during the hottest part of the day so that the ants would be in their burrows. The ants could smell the men coming to steal their gold, and would rush out to chase them away.

How did such a story get is start? We cannot say for sure, but it is possible that ants have brought up small pieces of gold while constructed their homes. A common archaeologists’ trick is to examine ant hills because the inhabitants sometimes excavate beads and other small artifacts from under the surface. Maybe somewhere the tiny, hardworking insects brought up enough gold to start the legend of the gold digging ants? Unlikely, and scholars also suggest that a linguistic confusion is responsible for the legend. Gold sent to India from Tibet was once called paipilika gold, while the gold supposedly dug by the ants were known as pipilikia gold. Maybe the gold digging ants were really Tibetans.

Beryl and diamonds, pearl and coral
As eager as the Romans were for gold, they were even more infatuated with beryl and pearls. India was glad to supply both.

The Roman savant Pliny in his Natural History said that beryls came only from India. There he believed they were all shaped into hexagonal prisms, though some authorities claimed that was their natural form. The Indians pierced them and strung them on elephant hairs.

Beryls were very special because they were the hardest materials that could be made into beads, harder than virtually any mineral except the corundum gems and diamond. Of course, the beryl beads were not formed by men; the natural hexagonal crystal shape was retained, and they were merely drilled lengthwise to be strung. The beryl mines of India were located in Coimbatore district in the south. So important was this industry that the largest hoards of Roman gold coins in India have been found there. This fact alone speaks for the tremendous demand for beryls in the Roman Empire and the gravitational pull of the mining area for Roman money.

The other secret in the export of beryl beads was that India could drill them despite their hardness. This calls for a diamond, and India was the principal source of diamonds for a long time. It is uncertain how long they were known in India, but the Rig Veda, the oldest book in the world (about 1500 B.C), mentions vajra, the thunderbolt with which the god Indra slew his enemies. Some 700 years later in the Atharva Veda, vajra had become a minor deity, the chief of the scathers, doing more than harm to enemies than any other god. Vajra could cut even the mythical Asuras, who bound men by slinging iron nets around them. The word vajra in later Sanskrit means diamond. Was the god Vajra of the Atharva Veda also a diamond, able to cut the Asuras iron nets? If this is correct, it means that the Indians recognized the cutting power of diamonds quite early.

In any case, the Indians were the first to use diamonds industrially. Double-tipped diamond drills were used to perforate quartz and chalcedonies at Arikamedu, in southeast India, occupied from the third century B.C to the third century A.D and it seems that all stone beads there were perforated with these drills. This use was recognized in the Greek and Roman world at least by the first century A.D. The earliest reference to diamonds in China was in A.D 114; they were first called chin-kang, which means gold hard or metal hard, the Chinese rendering of vajra.

The early literature on diamond is full of myths. Epiphanius, a fourth century bishop of Cyprus, was first to relate that diamonds were found only in one valley densely inhabited by poisonous snakes. To retrieve them, men threw pieces of meat down and eagles swooped in and took the meat to their nests. Diamonds stuck to the meat when it landed on the valley floor, and could be retrieved (though not without considerable risk) by killing the eagles or raiding their nests. The story became widely circulated. It is found in Chinese texts by 510 A.D, was part of the lore of the Arab hero, Sinbad the Sailor, and was recounted by Marco Polo 900 years later. Some scholars have suggested that it echoed sacrificing an animal before looking for diamonds, but this has no basis in fact. It seems more likely that it was a tale circulated by the Indians to discourage outsiders from raiding the mines.

Roman women (and a few men, much to Pliny’s disgust) adored pearls. Pearls are found in the Persian Gulf, but also along the southern Indian coast, especially in the Palk Strait and Gulf of Mannar. There are no accounts from Roman times as to how the pearl fishing was conducted. Marco Polo described the scene in the thirteenth century, and in 1797 Le Beck left a more detailed report. Their accounts are probably similar to the way pearl fishing was done in early times.

The center of activity was the deserted village of Condatchy, which sprung to life during the fishing season. The divers were fishermen from along the Indian coasts. They and merchants, brokers, and common people hoping for sudden wealth converged on Condatchy despite brackish water, the hoards of beggars who followed the crowds, and what was described as overpoweringly disagreeable odors.

The small diving boats held twenty one men: ten to dive, five to handle the diving stones and nets, and six to row. The divers would not enter the water until anti-shark magic was performed. After that, a net attached to a stone was dropped off the boat and the divers held their breath and plunged in. While diving they hung onto the cord that attached the nets and stones to the boats. Each diver stayed under about two minutes, descending fifteen to thirty meters.

The shells were opened on the shore, and the pearls sorted with small perforated brass plates or weighed on scales. Common people bought shells from the brokers to open themselves, hoping for a rich prize. During the 1797 season day laborer paid two pennies for three shells and found one of the biggest pearls of that profitable season.

The men who drilled the pearls made very little money, considering the fortunes they handled, but worked swiftly and deftly. The pearls were put in a hole at the bottom of a small, soft, wooden, up-turned cone which sat atop a short tripod. A metal drill bit hafted in wood was held with the left hand while the right hand worked a small bow back and forth. The worker dipped the little finger of his right hand into water in a coconut shell to drip over the pearl to keep it cool while drilling. The remarkable dexterity needed to perform all these operations at once could only be acquired with long practice.

Though it was well known that pearls came from oysters, there was still an air of mystery surrounding them. Aristotle thought that pearls were oyster hearts, and the Roman polymath, Pliny, wrote that oysters would “Yawn and gape…(then) conceive a certain moist dew as (sperm)..and the fruit of these shellfish are pearls.” Centuries later there were still questions about oysters: Did they walk on the sea floor? Were pearls soft in the shell?

The gem trade between Roman and India was not entirely a one-way street. The Romans controlled a material which the Indians found particularly desirable: precious red coral. A Greek sailor of the first century wrote about his voyages in The Periplus of the Erythraean Sea, telling us that Roman coral from the Mediterranean was much in demand in India and China, where it was used for ornaments and various medicinal purposes.

In Roman times coral was the major trade product going from Europe to Asia. Indians had been in love with coral long before Roman contact, and stayed in love with it longer after the Romans had gone. It was a staple of commerce between medieval Egypt and India. When the French jeweler, Jean Baptiste Tavernier, visited India in the seventeenth century, he noted that though coral was only semiprecious in Europe, it was precious in India and to the north. Even in the early twentieth century India was still the world’s greatest market for the red gem of the sea.

The nature of coral also defied the experts. As late as the seventeenth century, coral was being classified by early botanists as a plant.

The quartz gems
Diamonds, pearls and beryl were eagerly sought in the Roman Empire, and Roman gold coins and coral were welcome in India. These were an important segment of the ancient trade between these great civilizations. However, in terms of sheer bulk these products were only a small part of the ancient East West gem trade. The greatest amount, and in many ways the most important, was in a material not as rare as diamonds or pearls, but still of great beauty. We now regard it as semiprecious, but the ancients made no distinction between precious and semiprecious.

The quartz minerals provide us with more gems and jewels than any other minerals family. The Indian agate gem industry was centered in the west, especially the state of Gujarat. It supplied carnelian to Mesopotamia 2000 years before Romans, and even in our day is the major supplier of such beads worldwide. Along with carnelian, the mines located along the River Narmada, supply banded agate. Both the carnelian and agate nodules are found in a layer of red silt that was deposited with the stones when they were washed out of the Vindhya Mountains aeons ago. The deposition stopped about 22000 years ago. In contact with this red silt, the stones have absorbed iron. When they are heated in a muffled (reducing) furnace the iron turns to red, giving us carnelian and sardonyx. This is the spot that the Roman geographer Ptolemy called “The Sardonyx Mountain.”

There was another important gem cutting center in ancient India, which had close contact with Rome and produced some of the finest semiprecious gem stones ever seen. The Romans called it Podouke (with variations), as close as they could get to the name Puduchcheri, which survives today in the name of a nearby modern city of Pondicherry. The ancient city is now better known as Arikamedu, a name given to the ruined site by the local villagers, meaning “The Mound of Arukan”.

Whatever it was called, Arikamedu was a bustling manufacturing and shipping center in the early centuries A.D. The Romans had an emporium there, a place for Roman merchants to live and do business. Arikamedu manufactured several products the Romans wanted, such as colored cloth and leathered goods. But the real wealth of the city was in gems and costume jewelry of both glass and semiprecious stones. It may well have been an important market for beryls and pearls. Whether these were a large part of the trade is not known, but we do know that the glassmakers of Arikamedu took advantage of the Roman fondness for beryls, imitating precious stones, beryl in particular. It wasn’t that they colored rock crystal, but that they knew to make tubes of glass and paddle them into hexagonal shapes to imitate beryl.

Foremost among these gems trade from Arikamedu was onyx for Roman cameos, small carvings in low relief on a material with differently colored layers, which leaves figures against a contrasting background. The Romans were crazy about these handsome jewels. Pliny mentioned their popularity and said that cameo cutting was a new art. This was probably because the sea route to India had been newly opened, and the cameo material was available in bulk for the first time. Cameo production was encouraged by the emperors themselves, and several of the Caesars had magnificent collections of them.

The Arikamedu lapidaries excelled in making fine black and white onyx for these cameos. Onyx is extremely rare in nature. Man has to help out if he wants it. The onyx of Arikamedu began as plain, banded grey and white agate. The grey bands are more porous than the white, and when agate is soaked in a sugar solution or honey, it absorbs some sugar. When the stone is heated afterwards, the sugar carmelizes, leaving brown and white bands. If it is put into sulphuric acid, the sugar is carbonized, making black and white onyx.

Arimamedu was apparently the first place to make black onyx. The lapidaries sold much of it to Rome. They used it themselves to cut beads and other products, including thin-walled onyx bowls or cups, but most of the onyx found in the archaeological site was made into flat pieces, ellipsoidal in shape, suitable only for cameo cutting.

Turning agate into onyx was not the only trick the Arikamedu beadmakers knew. Another favorite stone was amethyst; many beautiful amethyst beads have survived made in a lively style with an excellent technique. Poor quality amethyst can be treated to produce a different gemstone altogether. By firing amethyst in a complex process, the golden yellow citrine results. Again Arikamedu seems to be the first place citrine was made, and the stone took its place along others as a major raw material for beads and gems.

Other stones were also worked at Arikamedu. Garnets were polished for cabochons to be set into metal jewelry. Rock crystal quartz and carnelian were very popular, and we occasionally find smoky, rose and green crystal quartz, jasper and opal used for beads. The semi-translucent green prase was also cut in quantity.

The fourth century Greek geographer Dionysius Periegetes must have had Arikamedu in mind when he wrote, “Among the courses of mountain torrents (the Indians) search for precious stones, the green beryl, or the sparkling diamond, or the pale green translucent jasper, or the yellow stone, or the pure topaz, or the sweet amethyst which with milder glow imitates the lure of (royal) purple.” The green jasper and the yellow stone are doublets prase and citrine and, along with the sweet amethyst, were among the most important of Arikamedu’s products.

The raw stones for the Arikamedu lapidaries were not locally available. They were transported hundreds of kilometers from the mouths of the Krishna and Godavari Rivers on the east coast of India or from inland areas. Though the stones traveled before they reached Arikamedu, the trip would be nothing compared to the one they would make after being fashioned and sent to the Roman Empire.

The lapidaries were extremely skillful at their occupation. Beads, cabochons and cameo blanks were made there, as were finger rings, cups or bowls, ear reels and perhaps bangles. All these required considerable skill. The bowls/cups, bangles and finger rings were cut out with large diameter drills (perhaps bamboo), aided with abrasives. Circular striations from the rotary motion of the drills can still be seen on unpolished specimens.

Another key aspect of this ancient industry was its organization. One of the most astounding things about Arikamedu is that beads were apparently made to preconceived patterns, not only shape, which we would expect, but even in size. Measurements of the collar beads (with extra material around their apertures) show that some types had very uniform dimensions. One group differed no more than 0.2 and 0.4mm in width and length, while another group differed by only 0.8 and 1.1mm in length and width. Even 1.1 mm, the largest of these differences, is very small. The precision of the Arikamedu lapidaries is evident.

The cameos were not cut into form in India. This was done in the Roman Empire, not because the Indians could not do the exquisite work, but because the Romans insisted on portraits of their own emperors and gods. A few finished seals have been found at Arikamedu, but it is thought that they were made by Roman or Greek artist living there.

The superior craftsmanship and excellent materials employed at Arikamedu are more difficult to describe than to picture, and the best way to appreciate this work is look at the plates accompanying this article. As beautiful as some of the pieces are, however, keep in mind that the finest work was not lost or discarded in the city for archaeologists to uncover 2000 years later, but shipped to the West as an integral part of the ancient and long lived East-West trade in jewels and gemstones.

The Diary Of A Carbon Rationer

BBC News writes:

The BBC News website asked Carbon Rationing Action Group member Peter Robinson to describe how his efforts to reduce his carbon footprint affected his daily routine.

Getting up: Don't put the light on in the bedroom; just open the curtains slightly to give a bit of light. This way you avoid losing too much heat through the windows. In the shower: Use a jug to collect hot water to shave in, to avoid heating more water to fill the washbasin.

Downstairs: Our kids will open the curtains rather than turning the lights on.

Breakfast: No lights on in the morning. Fill the kettle with the amount we need, ie a cup each for me and Sarah.

Work/school: Cycle or walk to work. Sarah and the children will walk to school most days, and then Sarah cycles on to work. Use the bike at work to go to meetings or visit other campuses.

Finishing work: Switch everything off standby and encourage colleagues to do the same.

Teatime: Spend a lot of time in the kitchen rather than moving a lot around the house, so as to avoid having to switch more lights on than necessary. We try to only light one half of the kitchen at one time. We are gradually replacing our incandescent light bulbs with energy-saving ones.

No TV: We don't watch TV at all, and the kids don't watch videos or DVDs during the week. But there's unlimited viewing for them at the weekends.

If watching DVDs or videos, turn down the dimmer switch really low.

On the computer: Turn the broadband connection on and off only as required. Remember to switch lights off in other parts of the house if they're not needed.

At or after bedtime: Only use the bathroom upstairs, as there's just enough light from the street light outside to see by.”

More info @ http://news.bbc.co.uk/2/hi/uk_news/magazine/6636521.stm

8am: Shower. Save The Water. Save The Planet

Here is a interesting story about energy conservation. Gemologists, gem dealers, jewelers and consumers may want to give it a try.

(via BBC News Magazine) Robert Greenall writes:

Would you switch everything off and rely on natural light to save the planet? It's the only answer for the families going to extreme measures to cut emissions. Most families get up in the morning, switch on the lights and start their ablutions. The Robinsons do not.

The Robinsons get up, leave the lights off and open the curtains a crack so some light gets in but little heat escapes. This is the world of "carbon rationing".

The term may fill some people with horror - conjuring up images of wartime austerity measures and queues for bread and sugar. For others it may suggest green fundamentalists forcing us to swap our central heating for woolly jumpers and run our cars on chicken dung.

A recent poll suggested only 28% of Britons thought the idea of setting mandatory limits on individuals' carbon emissions - raised by Environment Secretary David Milliband - was socially acceptable, even though most feel lifestyle changes are needed to reduce the impact of climate change.

But the term does not trouble Peter Robinson, and dozens like him around the country who have signed up to voluntary groups whose aim is to substantially reduce the CO2 their members are releasing into the atmosphere.

These Carbon Rationing Action Groups advise their members, known as Craggers, on how to minimise energy use. The Robinsons have eagerly set about finding ways to cut their personal energy use, many of which have also proved financially beneficial.

"It's only when you stop and start looking that you realise that you do waste a lot of energy, not out of spite or just being lazy or anything, it's just your normal lifestyle," Peter says.

"Our lifestyles were very energy-rich whereas now... there are things you can do in your life that don't stop you having a really nice time... but you can still make really substantial savings.”

"It's not draconian, you're not leading the life of a monk, it's just stuff that's really easy to do."

The 36-year-old school administrator may not think it is draconian but there are some who would raise an eyebrow at the prospect of using only the upstairs bathroom during the hours of darkness and relying on ambient light from streetlamps.

But Peter has been an enthusiastic "cragger" since joining his local Crag, in Worcester last year. Though he, his wife Sarah, and children Jacob and Molly, have been actively trying to reduce their carbon footprint for some time, he believes being members has helped to focus their minds on the task in hand.

"Being involved in the Crag... has really made a difference - monitoring how you produce your carbon... is what really has driven me and enabled us to look at what we do, how we live our lives, make those savings," he says.

It is easy to see the Robinsons as driven. They do not watch television, but for reasons that have nothing to do with the environment. Their children are allowed to watch DVDs at the weekend but the brightness control has to come down.

Developing habits is the key, Peter says. He described how he once visited a prison with a group of psychology students.

"One thing you notice there is that each time any of the prison staff went through a door they would close it and lock it, it becomes second nature. And when I started going round at home turning lights out it reminded me of that routine."

Most of the family's savings have come from using less heat (turning it off altogether from April to October and restricting its use at other times), less light and turning off electronic equipment at the wall. Peter has also pledged not to fly this year.

He says they reduced their personal carbon emissions from 12.7 metric tons in 2005 to 10.9 in 2006, well below the national average. He is hoping savings this year will have knocked another 10% off their emissions by December.

Financial penalties
Frustratingly for him, his local Crag has not offered any guidance or reduction targets. But in nearby Hereford one of the first groups to be set up recently finished its carbon "accounting" for the year April 2006 to April 2007.

It set a limit of 4.5 tons per person. Some Crags have elected to impose financial penalties for those who exceed the limit, but Hereford decided not to. Carpenter Steve Ball, 36, who joined Hereford Crag last year, found a combination of his car use and a flight to Slovenia had pushed him well over the limit to more than seven tons.

But although he had never previously calculated his footprint, he believes changes he has made have already cut deeply into his emissions - for instance, converting his car to run on a biodiesel mix and resisting regular calls by friends to fly off to Tallinn or Prague.

Like Peter, Steve has taken small steps across the board - like using a small motorbike for some journeys or insulating his converted loft. He plans to insulate his floor as well, but his dream is to build afresh.

"Renovation is quite a hard thing to do, to make an old house efficient energy-wise, but I'm looking into building a new house," he says.

Both Peter and Steve have made massive changes and are prepared to go further. But they both seem wary of the Crags' ultimate aim - to reduce personal carbon emissions by 90% by 2030, which the movement says is necessary to avoid dangerous and potentially runaway climate change.

"We would struggle as a family to get 90% cuts," Peter says.

"If it's do-able, then great idea," says Steve. "We can strive for it, but whether or not it's realistically possible I don't know."

One thing is sure. If anyone can do it, it's the Craggers.

More info @ http://news.bbc.co.uk/2/hi/uk_news/magazine/6635759.stm

Tuesday, May 15, 2007

CrystalSleuth

The windows-based software, called CrystalSleuth, may become an useful tool for analyzing and interpreting Raman spectra and powder X-ray diffraction data. The software may be able to compare multiple spectra and identify an unknown sample utilizing the online RRUFF project database.

With the continued technological advances portable Raman spectrophotometer may become even smaller and affordable in the future for gemological studies or other applications. This, combined with the free CrystalSlueth software may become a user-friendly tool for practising gemologist and gem dealers.

Raman spectral library is freely downloadable from the RRUFF Project web site @
http://rruff.info/about/about_software.php

Trapiche Tourmaline From Zambia

Well formed crystals of green tourmaline have been found with a growth pattern similar to trapiche emerald and ruby from Kavungu mine in the vicinity of Jivunda in Chief Sailunga's area, southeast of Mwinilunga in northwestern Zambia. Those who are not familiar with the crystal specimens may confuse for emeralds because of its color and patterns. The experts believe that the trapiche-like appearance may be due to skeletal growth with black carbonaceous substance, most likely being graphite, that may have been embedded with other impurities during the growth of the crystals. Chemical analysis indicate that the tourmaline is uvite and is colored green by vanadium. Facet quality specimens are rare due to the dark color of the tourmaline.

GemQ

when you are curious
ask this
simple question
what are gemstones?

where do they
come from?
why are some
stones so expensive?
why do people
go the extra mile
to find them?
the gemstones
speaks to you
in colorful languages
the mineral way
the gemstone way

gemstones are synonym
for love and status
symbol of commitment
intended gifts for a few

gemstones have
special status in
our culture
it is based on
an illusion
a few gems appreciate
value with time

some believe
gemstones are nature’s
gift to mankind
some believe they
are from the gods
of this universe
some believe they
are for the people
by the people
to share and enjoy
rarity and beauty

Monday, May 14, 2007

Harper

Memorable quote from the movie:

Lew Archer (Paul Newman): The bottom is loaded with nice people, Albert. Only cream and bastards rise.

His Jewellery Box

(via Live Mint) Parizaad Khan writes:

From pendants to gold bracelets and lapel pins, men’s fashion focuses on accents

As an architect, it’s a given that Jimmy Mistry, 34, pays attention to detail. But he takes it a step further when it comes to grooming. He spends a fair amount of time each morning coordinating his jewellery and accessories. So, apart from his white topaz and white gold ring (“very unobtrusive, it goes with both formals and informals”), he pairs a thin gold Italian bracelet with his steel Rolex, or matches his blue leather strap Audemars Piguet with a blue lacquer and steel pen. He’s figured out various other combinations, which he changes daily.

Mistry is a member of that group of men who were not scarred for life by Bappi Lahiri, so wearing jewellery doesn’t put him off. “I’m fond of accessories and like expressing myself this way.” His tip: “Stick to what you can carry off. I wouldn’t try a diamond pendant, though it looks good on Vijay Mallya,” he says.

Jewellery for men is no longer restricted to stones recommended by astrologers, gold chains or cuff links. It now includes materials like wood, steel, leather, semi-precious stones and even square-cut diamonds, as accents.

“All men are closet jewellery lovers,” believes Mumbai-based jewellery designer Anita Vaswani. “From the Zegna-wearing guys to metrosexuals—they all love embellishment,” she says. She’s currently working on a men’s line for her label, Stoned. Vaswani’s male friends keep demanding more, so the idea for an all-male line was born. But it’s not for the faint-hearted: hunks of turquoise and charms strung with Rudraksh beads.

On the other hand, Bollywood’s favourite designer, Farah Khan, has sobered up when it comes to sketching for the boys. She launched her male line last year, after asking corporate and film friends for inputs. “I found that most men weren’t afraid to experiment, but they like to keep it masculine, with geometric shapes or straight lines,” she says. She says her men’s line was a success because the timing was right. “Maybe it wouldn’t have been successful five years ago. It used to be macho not to wear jewellery, but now it is,” she says.

Khan isn’t off the mark. When Manali Vengsarkar, jewellery designer and cricketer Dilip Vengsarkar’s wife, launched her collection earlier this year, she presented the Indian cricket team with a long, tablet-shaped pendant strung with a leather thong. They were well received, so Vengsarkar’s men’s line will be launched before Diwali this year.

One of Vaswani’s clients is 31-year-old restaurateur Aditya Kilachand. He believes the days of gold chains are passé; today’s trend is to wear one statement piece, be it around the neck or wrist. Whether he’s working at his South Mumbai restaurant, Tetsuma, or partying with friends, he puts on three or four thin Rudraksh bracelets. “I like to leave my jewellery on all the time, I don’t wear things I have to change too often,” he says.

Mistry says he prefers to change every day and he accessorizes mostly when he’s at work. “In the evenings, I try to be as casual as possible,” he says.

Biren Vaidya, jewellery designer of the Rose Group, designs for those who don’t believe in being casual. His male line, Rose by Bee Vee, has contemporary pendants and bracelets, crafted from rubber, wood and steel. But his speciality is the flower or bee-shaped diamond lapel pin, worn on the lapel of a jacket or a shirt collar. “It’s a more subtle statement for those times when you can’t leave your shirt buttons open and wear a pendant. It always gets noticed and appreciated,” Vaidya says.

More info @ http://www.livemint.com/2007/05/12000525/His-jewellery-box.html

A Primer On Life Skills

2007: I think gemological schools should train their graduates on a similar wavelength. Many students lack soft skills, life skills and are totally clueless + unemployable. All they want is money, money, and plenty of money.

(via Business Standard) Prakash Iyer writes:

It was the summer of ’86. And as I, and the rest of the graduating batch, walked out of the hallowed portals of WIMWI (ah, the Well-known Institute of Management in Western India), you could sense that we were probably echoing Bryan Adams’ words as we looked back on our two years on campus: Indeed, those were the best days of my life!

We learnt the fundamentals of management. We learnt to draw up business plans, and evaluate advertising, and discount cash flows. More important, we learnt to stretch ourselves, and structure our thinking. We learnt to work hard. To compete. To win. And we made friends!

B-schools do a terrific job of equipping us with business skills. What’s missing, perhaps, is a primer on life skills. We emerge competent to deal with the complexities of running a business — but not quite as adept at managing the business of running our own lives.

Here then, in no particular order, are four life skills I wish they had taught us in B-school.

Goal setting: I wish every student passing out of B-school would walk out with a set of written goals for himself. A set of goals that define what each of us want to do, be, have and achieve. That would include financial and career goals for sure, but would also cover other key areas such as family, health, relationships and personal interests. Goals provide direction and discipline, helping us stay focused on what is really important to us. Without those goals, we tend to drift — and wonder why we sense a strange emptiness even as the next promotion beckons. And as the saying goes, if you don’t know where you are going, any road will take you there.

Communication: The best ideas and thought are of little use if we don’t learn to communicate them effectively. Learning to use the right words at the right time, to empathise and listen are priceless skills no one teaches us. We master an assortment of financial ratios but forget the message God sent us when he gave us two ears and one mouth: listen more than you speak. And making presentations is a key part of business life — yet you find bright young managers fidgeting nervously and reading out every word of a text-heavy and hastily prepared PowerPoint slide. If only they had been taught communication and presentation skills!

Good health: Corporate waistlines are expanding almost as rapidly as company bottom lines. And between early morning flights and late night conference calls, no one seems to have the time to take care of their own bodies. The games we grew up playing become the stuff we watch on TV. And our idea of a long walk is the trek from the corner room to the elevator. Perhaps B-schools should inculcate the habit of an hour in the gym every day. And the pursuit of a sport, say, every week.

Work-life balance: No man on his death-bed ever said “I wish I’d spent more time in the office.” Watching your child grow up, spending time with loved ones, being there at those special moments in other people’s lives — all these can probably give you as much joy as a deal clinched or a market share point gained.

“What would you do differently if you knew you had only six months to live?” We could all probably answer that one quite easily (spend more time with the family, play with the kids, take off on that vacation to the hills, write that book …). Alas, none of us really knows when precisely we have only six months to go.

B-schools teach us how to become change agents. We learn how to change the world, the consumer, the organisation, the works. But we don’t quite learn how to change one key piece: ourselves. Learning to change ourselves, our thoughts, our beliefs, and our actions can often be the biggest and most effective change we can make!

Prakash Iyer graduated from the Indian Institute of Management, Ahmedabad in 1986

More info @
http://www.businessstandard.com/common/storypage_supp.phpautono=283680&leftnm=1&subLeft=0&chkFlg=B-schools

Identifying Opal Doublets

(via Gemological Digest, Vol.2, No.4, 1989) Grahame Brown writes:

Abstract
Opal doublets have in the past been produced mainly to utilize material otherwise too thin for cutting solids. They were not normally produced for fraudulent purposes, and identification was simple, due to an even join between opal and backing. Today, a new and more sinister type of opal doublet has appeared. Produced by bonding a rock backing to an irregular piece of precious opal, the result is a stone which looks very much like Queensland boulder opal, even to the trained eye.

In this article, the author discusses both the history of opal doublets, as well as the latest incarnations, and describes useful techniques for recognizing these frauds.

Introduction
The opal doublet is a cabochon-cut composite stone. It consists of two components: a domed ro flattened top of precious opal and a base of dark colored, light-absorbing material.

While natural opal doublets can be cut from some precious opal that occurs as near parallel layers of either opal potch, opal-ironstone, -sandstone, or –mudstone, most commercially marketed opal doublets are manufactured products that have been deliberately assembled, preformed and polished by man.

Origin
Available evidence suggests that the assembled opal doublet of Australian origin. It was first devised and manufactured in 1897 by miner-lapidaries on the remote, arid north-west New South Wales opal field of White Cliffs, 1000 km north-west of Sydney. The reason why these 19th century opal miners chose to manufacture the opal doublet was one of simple economics: only about 5 percent of the production output at White Cliffs was gem quality white opal. So, a use had to be found for the many thin veins of precious opal that could not be used for cutting solid opal cabochons. The opal doublet, made by cementing a thin layer of precious opal to a backing of dark grey opaque potch, was the simple, yet economic, answer to the low yield of precious solid opal from the White Cliffs field.

Method of manufacture
Today, opal doublets are commercially made for at least three reasons. First, the mined precious opal may be too thin to cut a solid opal. Second, the opal may have such a pale body color that its play-of-color (and value) could be enhanced by backing it with a suitable dark colored light absorbing material. Finally, by adhering a suitable backing to a thin layer of opal, the resulting composite could then be used to imitate opal of much greater value and rarity.

Choice of opal
Opals suitable for doublet manufacture should display the following characteristics:

- Freedom from clearly visible flaws (cracks, crazing, webbing, sand or gypsum inclusions, unsightly potch bars).

- A reasonable transparency, allowing light to penetrate through the opal top to the light absorbing backing.

- A distinct and rather muted play-of-color. This play-of-color is enhanced by being strongly contrasted against the dark backing.

- Sufficient thickness of precious opal to allow a flat plane-of-attachment to exist between the precious opal top and the light absorbing backing.

Consequently, flatish fragments of white or other pale-colored jelly or crystal opal make the most striking opal doublets. The use of opaque whitish to grayish opal only creates dull, lifeless doublets that display a poor play-of-color.

Choice of backing
The best backing for opal doublets is opaque black potch from Lightning Ridge. Due to the rarity of Lightning Ridge black potch, other opaque black backings, such as black glass, black plastic, obsidian, and even black onyx have been used to produce opal doublets imitating black opal. Care should be taken when choosing black backings for opal doublets: a backing with a coefficient-of-expansion differing from that of precious opal (e.g. black onyx) could fracture the doublet if moderate heat is applied to the finished composite.

With increased demand for dark Queensland boulder opal as an alternative for the increasingly rare and valuable Lightning Ridge black opal, manufacturers have begun producing opal doublets intended to imitate Queensland boulder opal. The precious opal component of these doublets may consist of thin, flat segments of Queensland boulder opal, whitish crystal opal shell pseudomorphs from Andamooka (South Australia), translucent to transparent whitish opal from Coober Pedy, Mintabie (South Australia) or White Cliffs (NSW). Backing for these doublets includes ironstone, dark-colored sandstone, and mudstone, commonly associated with Queensland boulder opal. There exists also a composite backing made by incorporating crushed fragments of the above materials into a black pigmented epoxy resin plastic.

A black backing is unnecessary when a doublet is made only to provide thickness and strength to a thin sliver of precious opal displaying a valuable color pattern. In such cases, grey potch, plastic or glass usually suffices as suitable backing.

Choice of adhesives
To permanently affix the top and backing of an opal doublet, most manufacturers use an epoxy-resin adhesive that is pigmented by carbon. Setting times of these adhesives vary from 5 minutes to 24 hours.

Methods of identification
Conventional opal doublets are identified traditionally by observing the presence of:

- Three components: a top of precious, natural opal; a backing of dark colored potch opal, glass, plastic, ironstone, sandstone, mudstone or iron stone filled black epoxy resin; a thin layer of adhesive permanently joining the top to the backing of the cabochon.

- A flat, junction-plane between the precious opal cabochon top and backing. This junction can vary in thickness. It often has gas bubble inclusions entrapped in the adhesive.

- Included, somewhat squashed, bubbles within the junction-plane of the doublet. The visibility of these bubbles is increased when the epoxy resin is viewed through the transparent opal top with the aid of an intense fiber optic light source.

- Occasional evidence of a pigment layer used to darken the flat-ground undersurface of the precious opal top of the doublet.

- Evidence of lifting of the top of the doublet from its backing, if the components are poorly adhered.

It is more difficult to identify some of the recently manufactured doublets designed to imitate boulder opal. These imitations are characterized by:

- Very thin, non-planar junctions between the top and the backing of the doublet.

- Junctions that are relatively free of included bubbles within the epoxy resin.

- Backings that are cut from coarse-grained sandy Quilpie ironstone/sandstone, or dark fine-grained banded Winton mudstone. Some of these backings are also included by thin anastamosing veins of precious opal.

To differentiate these effective look-alikes from the natural Queensland boulder opal they imitate, gemologists must be prepared to examine closely the junction separating the two components of a suspect doublet. In particular, one should look for identifying visual characteristics of Queensland boulder opal, such as:

- An irregular epoxy resin-free junction between the precious opal top and the ironstone, sandstone, or mudstone base of the cabochon. No visual evidence of an adhesive bubble-included junction should be seen when this interface is examined through the natural top of the boulder opal cabochon. Fiber-optic illumination greatly assists a detailed examination of the junction of most opal doublets.

- Tongue-like projections of precious opal that penetrate the sedimentary rock base (matrix) of the cabochon.

- A cabochon base formed from dark colored sedimentary rock (sandstone, ironstone, mudstone) that does not contain black plastic matrix or included gas bubbles.

Conclusions
It is not difficult to identify conventional opal doublets, made by cementing with black epoxy resin a top of diaphanous light colored jelly or crystal opal to a backing of dark potch, glass, plastic, or sedimentary rock. A simple 10x hand lens should quickly disclose the tell-tale, uniformly thick planar junction that is a feature of these composite stones. Hand lens or low power microscopic examination of the junction of conventional opal doublets should reveal gas bubble inclusions and/or solid particulate fillers within its content of black epoxy resin adhesive.

It is somewhat challenging to distinguish cabochons of Queensland boulder opal from their newer-manufactured doublet imitations. This is because the adhesive-filled junction between the precious opal top and the ironstone, sandstone or mudstone backing of these doublets is extremely thin, highly irregular in profile, and is made much less conspicuous by incorporation of finely ground particulate matter in the black epoxy-resin adhesive filling the junction. Careful low power microscopic examination of the junction area is required to identify the distinctive features of this effective look-alike of Queensland boulder opal.

How Dr Williamson Nearly Missed Finding The Mwadui Diamond Pipe

2007: Here is a remarkable story of a diamond prospector of a different generation. This can happen even today.

(via Indiaqua 23 1979/4)

Unpalatable to Tanzanian pride as it must be it does seem as if the discovery of their greatest natural asset, diamonds, is owed to a combination of Irish independence and Canadian frustration. Irish because Dr John Thorburn Williamson was of that ancestory, and Canadian because logging n Quebec did not appeal to the future finder of the diamondiferous Mwadui diamond pipe.

It is also, it seems, a subject which an Italian called Signor Bondini prefers to dismiss as one consequence of Italian reverses in the last World War—since he was interned at the moment of his own discovery at Mwadui.

Mr G J du Toit’s unpublished manuscript states that Williamson “took to Geology by chance,” and obtained a B A degree with Honors. Post graduate work on Newfoundland minerals enabled him to achieve an M Sc degree in 1930, and subsequently a Ph D in 1933, as a result of a thesis on chromite. This work brought him to contact with the doyen of Canadian geologists, Dr Joe Bancroft, then Consulting Geologist to the fledgling Anglo American Corporation of S.A.Ltd. After a brief job with the Quebec Gold Mining Corp., Dr J T Williamson said au revoir to his family and sailed aboard the Italian liner “Rex” from New York to Cape Town.

On arrival at the Cape he took the Rhodesian Express to Bulawayo and joined the Bechuanaland Exploration Co Ltd being seconded to Loangwa Concessions (N.R) Ltd based at Rhodesia Broker Hill. It was here that he made a few small gold deposit discoveries 7 years later further north in Tanganyika. He also discovered that a little lime in a scotch and water took away the brackish taste.

Break with De Beers
Legend has it that Williamson fell out with the Anglo American Group in 1935 and he went doggedly on to trace diamonds in Tanzania. The truth is that he joined a company which was seeking a geologist—Tanganyika Diamond & Gold Development Ltd. This company operated three small diamond mines at Mabuki and Kizumbe near Shinyanga Plain, found in 1913 and 1926 respectively. The diamond content of these mines was not attractive. This puzzled Williamson who developed a theory that garnets and ilmenite found in diamondiferous deposits were quite different from garnets found without the presence of diamonds.

Unsatisfied with £55 per month Williamson left “Tanks” in 1938, and brought the Mabuki deposit for a few hundred pounds. He also acquired malaria and black water fever—and an Indian barrister’s interest, Mr I C Chopra, who called his new client “the gentleman from the bush.”

Following his geological hunches Dr Williamson began to take the lone prospector role seriously and one night he sat up all night in a truck waiting to peg his claim at dawn at Kizumbe. An Italian, Mr Bondini, in the vicinity, was also on the diamond trail, but he spent his nights more enjoyably in bed. Also more rewardingly, because by 1939 Williamson was in a mood to quit Tanganyika. He contemplated joining the military service, but before be could achieve that he had to pay various bills to Indian storekeepers. His German creditors had mostly been interned.

Somehow his debts to Indian storekeepers save him. He was able to retain only a few African prospectors and on 6th March 1940 James, son of Anton, brought on his truck to base camp a large piece of ilmenite from the village of Luhombo—from a trench actually dug by the Geological Survey of Tanganyika. Williamson looked deep and long at that ilmenite—often an associate of diamond. From the ilmenite a 2 carat diamond was extracted. And James was of that moment included in Williamson’s will—unbeknown to either men.

Enter and exit a Roman prospector
At dawn on 7th March Williamson drove hell for leather to the spot where James had picked up the ilmenite—a place called Mwadui, and then to the District Commisioner to apply, and obtain, an Exclusive Prospecting Licence. A few days later Williamson applied for claims as ‘discoverer”, to 3 square miles north-west of Luhumbo village, Mwadui. Who appeared at the District Commissioner’s office but the Italian, Signor Bondini, to protest on the grounds he was there first. He was dispatched in the most appropriate British manner by being arrested and subsequently interned as an alien. This seem sag geologically since Dr Williamson later acknowledged that the Italian was his chief rival and implied he knew a lot about Mwadui diamond deposits.

Williamson proceeded to peg with uncanny accuracy the limits of what turned out to be the world’s biggest diamondiferous pipe. To sisal and cotton were now to be added diamonds—Tangayika’s principal products. And to the fairly simple, pleasure-loving Dr Williamson diamonds found within his pegged area were to add a fiendish complexity. Prospecting revealed substantial diamond finds, which Williamson, trusting few, took personally to the Mwanza Branch of the Standard Bank. In Mwanza he took the opportunity to call on his lawyer, Mr I C Chopra. They discovered they shared an Irish heritage—for Chopra had gone to Dublin from Gurjanwala at eleven years of age before settling in East Africa 21 years later, where his intelligence and public spiritedness earned him the C.B.E…

Williamson becomes a limited company to Socialist acclaim
By 1942 Williamson Diamonds Ltd had been incorporated with a capital of £200000 (400 shared of £500 each), Chopra subscribing for 1, Williamson’s brother got 100 free and the doctor paid for the balance of 299. Williamson was running the show, even to the extent of listing the weight and number of diamonds recovered by sunset each day. He grew thin and irritable, not fat and prosperous in the capitalist tradition. By 1944 Dr Joe Bancroft of Anglo American was on the scene and on behalf of Sir Ernest Oppenheimer offered £2m to Williamson for outright control of the mine. Williamson refused. Thanks to Italian prisoners of war being employed on the mine, Williamson, who referred to them as “these industrious little men,” began to see that Williamson Diamonds Ltd had a major productive role to play on the diamond stage. This realization was simultaneously shared by Sir Ernest Oppenheimer in Johannesburg.

By 1946 the British Colonial Secretary Creech Jones had visited Mwadui and left convinced Williamson was almost a teetotaler and that nationalization of his mine would turn African people off socialist doctrine. So Williamson ran his mine roughly as he pleased. It was a boisterous era in which physical feats were socially applauded. Williamson would turn up nightly in European Club—seldom in the Asian or African counterpart. He also developed a penchant for Peter Scott bird studies of stormy seascapes as well as Russell Flint’s paintings.

The Williamson story
The mining industry does not relish loners. Teamwork is the catchword. But in the case of Canadian geologist Dr John Thorburn Williamson—the diamond industry accorded him a special respect, supreme loner that he was. Had he not only discovered but also owned an enormous diamond mine his name would possibly by now have been fairly well forgotten. But it is not forgotten and his story continues to stir many a geologist throughout the Western world as he takes his first tentative step into bush, desert, outback, or jungle.

For the following excerpts from Williamson’s last ten years Indiaqua is indebted to Mr Gabriel J du Toit, a South African mining man who for 10 years was closely associated with the ‘Doctor’ in the development of the Williamson Diamond Mine.

Part 1 in Indiaqua 9 described Dr J T Williamson’s origins, his start in Southern Africa, his break from De Beers and his amazing discovery in 1940 of the world’s biggest diamond pipe, 361 acres on the surface. By 1947 Dr John Williamson was feeling on top of the world. The price of diamonds was rising fast, the Williamson Mine diamonds were of high quality, and there were several hundred persons employed at Mwadui producing several thousand carats per month.

Bachelor status for man and mine
This called for a celebration and Dr Williamson, then aged, 44, flew south to Johannesburg, to recruit mining engineers and metallurgists, security experts and medical assistants for his mine. During his stay, contact was made with the Anglo American Corporation’s Geological Department. Their interest naturally centered on the dimensions and yield of the Mwadui diamond pipe. Dr Joe Bancroft, the doyen of Anglo American’s geologists, proposed a joint prospecting programme. This was linked with an offer to participate in the Williamson company, whereby the doctor would receive £750000. The loner’s instincts reacted and Williamson returned to the mine that bore his name—determined that it should continue to do so, without partners.

The next scare for Dr Williamson was the British Labor Party’s plan to nationalize the mine. Only a direct appeal to the Colonial Secretary, Mr Arthur Creech Jones, caused those plans to be shelved. This incident spurred Dr Williamson to redouble his efforts in exploring and developing the diamond mine. The fiasco of the British Government’s nationalized East African ground nut scheme would not be repeated with his diamonds. However, problems at the mine were not long in coming—security became a great headache, ‘over mining’ of rich areas was not appreciated by the Government mining inspectors, and for a brilliant geologist the revelation that the pipe contracted sharply—in fact at only 50 meters the 361 acres on the surface shrunk to a mere tenth, while at 75 meters deep the pipe had narrowed to a thin dyke—must have been deeply disappointing.

Dr Williamson disposed of the mine’s production of diamonds through the Diamond Corporation Ltd in London as a result of the agreement made in December 1947. The course of this contract did not run smoothly and at one time Williamson Diamonds Ltd received no revenue for 18 months because of disputes, arbitrations and misunderstandings that plagued the functioning of the agreement.

Dr Williamson succumbs
In 1956 Dr Williamson was found to have advanced cancer of the larynx. Distraught, he proceeded to Montreal to stay with his sister, Mrs Mary Miller. Depressed by the endless Canadian winter he flew to Australia to meet his friend Mr Albert Joris, who was shocked by his appearance. From Sydney Williamson journeyed to Japan, Hong Kong and Singapore in search of earth moving equipment. Then he decided to visit Johannesburg. Sir Ernest Oppenheimer sent his personal aide to the Langham Hotel suite to invite Williamson to Brenthurst, the Oppenheimer home. Dr Williamson declined.

Weighing only 100 lbs. the Doctor flew to Nairobi, and on to his beloved mine. With a scarf wrapped around his neck he would take rides at night around the mine, hiding from the eyes of thousands of his employees. On Jan 8th 1957, aged 50, Dr John Williamson died. Sir Ernest had died only a few weeks earlier in Johannesburg. Dr Williamson left all his assets to his family in Canada. He had never married. Shortly after Williamson’s death, Mr Harry Oppenheimer, in his first big deal, flew to Mwadui and successfully negotiated for the purchase by his group of 50% in Williamson Diamonds Ltd, the government of Tanganyika acquiring the other 50%.

His successor as Chairman of Williamson Diamonds Ltd was none other than Mr Harry Oppenheimer, until succeeded 15 years later by Mr Timothy Apiyo, Principal Secretary of the Tanzanian Ministry of Commerce & Industries. Mr George Hunt, who had been appointed General Manager in 1958, was replaced by Mr Samuel Lwakatare in 1973, who had obtained an M.Sc in engineering from Dr Williamson’s old McGill University, Montreal.

Sunday, May 13, 2007

Graff Unmistakably

2007: Here is a 101 course for beginners from Laurence Graff, one of the most famous and successful jewelers in the world.

(via Indiaqua, 49, 1988/1) Natacha Vassiltchikov writes:

“The secret of my success…”, he said with a slight smile, “I would say first, hard work; secondly, devotion to the industry; and thirdly, reinvestment of the profits into the business. And then, of course, my satisfaction lies in the feeling I have for the gem. I always think that if I’m good to the commodity, it will be good to me.”

In these few words spoken without the slightest hesitation, Laurence Graff, fortyish, of medium build, with piercing dark eyes and ready smile, has summed up the essential qualities which have enabled him—in less than thirty years—to become the leader a new generation of jewelers in the world. The only decoration of the simply furnished but comfortable room in which he receives me is a portrait of himself. He emanates an unassuming though confident awareness of the exclusiveness of both his business and his clientele. He moves quickly, speaks quickly, and seems to have mastered the art of answering questions in the shortest, most concise, and at the same time, most non-commital manner. Yet while visibly an extremely busy man, he retains the courteous affability of someone who is willing to allocate the same importance and time to everyone.

Laurence Graff entered the jewelry business at the age of fourteen when he became an apprentice in Hatton Garden. This early start was not in response to any kind of vocation. It was the result of a common decision by a humble family of English origin who considered the diamond industry a good way of making a living. “It could have been anything else.”

He made his beginning in repairing, and gradually but quickly climbed all the steps of the trade. He soon created and sold his first diamond ring, the profits of which allowed him to produce two more, then three, and so on….until he was able to buy polished stones. At seventeen and a half he had to set up his own business. He gained initial official recognition in 1973 when he became the first jeweler to be presented with the Queen’s Award to Industry. This was followed by a further tribute when he received the 1977 Queen’s Award for Export Achievements.

Today the House of Graff deals in London—its central establishment—Geneva, New York, Tokyo and specified in the brochures, “worldwide by appointment.” It organizes exhibitions from South America to the Far East, and stages in London private viewings for royalty and other celebrities. By operating worldwide, it has acquired a selective clientele whose taste for stones of high and rare quality it seeks to satisfy.

The bulk of the business consists naturally of diamonds. ‘It is harder to find really beautiful gems among other stones. Whereas with diamonds one can actually deal at the top. Besides, the diamond is translucent, brilliant….It is also fascinating, because of its unique variety of colors and shapes….”

“Diamonds are my hobby,” Laurence Graff adds. “I measure their value not only scientifically but also inwardly, through feeling, with the heart.” This respect and reverence which he expresses for top quality stones is best reflected in the style which he confers to his jewelry. Extremely classical, he adorns his pieces with the simplest of settings, giving full scope to their bare and natural beauty. He vehemently condemns the marking of stones (a recent practice designed to thwart theft): “Why damage a flawless gem?” He also refuses to adhere to changing fashions and trends. Despite the rise in price which big stones have recently undergone, he does not believe in enhancing the appearance of smaller pieces by fitting them into heavier mountings. “We do not cater to changing taste…We expect our clients to come and buy out style.” Laurence Graff relies therefore primarily on a select but top rate clientele, to which he offers an ever-fresh supply of gems going across the whole range of colors and shapes. “We have to be in the front line all the time.”

Achieving this goal requires not only diligence, dedication to and love the stone, but also a sound sense of judgment and discernment. Laurence Graff is the first to recognize that the value of a piece of jewelry is relative. As he explains, every diamond is—in comparative terms—of high price. For a humble person the first half carat is expensive. At the same time, for a rich man, the first thirty carats is expensive. “The real challenge for us is not whether our client can buy one diamond, but whether he can carry on buying diamonds.” The obvious way to encourage this development is to convince people that diamonds are a store of wealth. But even failing this—as, for instance, during the crash of 1980—Laurence Graff is confident that “attraction of great beauty is endless and no matter what the cost, there will always be a buyer for even the most ‘priceless’ of jewels.”

The 1980 collapse was indeed a major disaster which profoundly hurt the business. Not only did it damage the diamond’s image as a secure investment—De Beers’ famous slogan “a diamond is forever”—but it affected the availability and price of the big stones which remained locked until the jeweler’s safes and bank vaults until the prices started moving up again. Laurence Graff admits that for several years he himself did not buy a single D flawless one carat stone. Another adverse consequence of the crash which he deplores is the disruption of the orderly level of supply which De Beers had succeeded in maintaining until then. Although the cutters keep complaining about the shortage of large stones on the market, Laurence Graff himself believes on the contrary that a certain degree of scarcity is healthy. He is, in fact, worried that the present level of supply may have risen again too high.

But he does not see the Far Eastern market as replacing that of the Arab countries. Graff has five franchise boutiques in Japan, which mainly sell lower priced articles. Laurence Graff has often been asked how he can part with jewels into which he puts so much love and work. He admits that each one of them constitutes a little part of his life. “It is like a baby, it becomes one of the family. I choose the stones, create the piece, live with it for a while, and it has to be a one hundred percent success for me to make up my mind to sell it. By selling the best pieces, we get the best clients.”

For all this, Laurence Graff never completely detaches himself from his rarest and most important stones. Indeed he has had made up a collection of some twenty to thirty perfect reproductions of his finest gems. In a time consuming operation, he has sought to retain their exact color, shape, cut and number of facets. As he smilingly concludes: ‘You asked me whether I grew attached to the pieces I create. Well here now you can see—just how every attached I get.”

Life's Lessons Learnt On The Sidewalk

(via Times News Network) Nikhil Hamrangani writes:

It is a regular evening on the Marine Drive. People are out with their walkman and Ipod. Couples on the parapet are locked in embrace. Everything is just as it should be here. But, across the road, is an unusual sight. On the sidewalk near Hotel Ambassador, in the dim light from a jewellery store, street children are sitting on newspapers. These kids are probably the same urchins who tug at your shirt to sell magazines, flowers or just utter the familiar line: "I am hungry." But, here on the sidewalk, they are learning. This is the transient classroom of Hamara Footpath, an informal group of young boys and girls who want to do something for urchins.

At the helm of Hamara Footpath is its founder, 24-year-old Shubhangi Swarup. "It is an open community effort where people from all walks of life are encouraged to step in and engage themselves with the street kids in any manner that is helpful," she says. Thrice a week, from 7.30 pm to 9 pm, volunteers assemble on the footpath facing a jewellery showroom and interact with the kids.

Some take it upon themselves to teach the kids Basic English and mathematics. Others bring with them colouring books and pencils or sing and dance along with the children. And, every few months, Hamara Footpath takes the children to films, circus or on a picnic. Last Sunday, for instance, they went to the zoo in Byculla. There has even been a football session at Oval Maidan, a Christmas party, and a paper-making workshop.

"The development of a child is a holistic process," Swarup says. "Just sponsoring their education or putting them in a home is not enough. They also need personal time, attention and love which is what we are here for," she adds.

The sidewalk classes see about 25 kids with five to 10 volunteers, picnics attract over 50 children, including a few of their street-dwelling parents. Money for such outings is raised by volunteers from peers by way of e-mails and oral communication. But it does not end there. Nearby chemists, general practitioners and shopkeepers also offer a helping hand by sponsoring medicines or performing medical check-ups.

Volunteers come from diverse backgrounds. Swarup did an M.Sc in violence, conflict, and development from the University of London. 24-year-old Taha Jodiawala runs a family business of construction products. ‘‘Hamara Footpath quashed my misconceptions about street children and the poor after I spent time and unwound with them,’’ he says. Then there’s 28-year-old graphic designer Nupur Shah, who is endearingly referred to as Dupar Didi by several children. She teaches children art and craft.

And, apart from the regulars — comprising IT professionals, dentists and doctors — passersby, too, often join the cause after observing Hamara Footpath in action. "Each volunteer with his or her unique thoughts contributes in a unique way, seeing a problem where the others have seen none," Swarup says.

Hamara Footpath’s success has even garnered the attention of groups in Chennai and Kolkata who wish to extend Hamara Footpath there and continue its mission.

Today, with more than 18 million kids on the street, India has the highest concentration of street children in the world. And the number is growing. Many of these children die young for want of simple care. Many of those who survive are consumed by the city’s underbelly. Hamara Footpath offers more than what is tangible. "To look at us as a group promoting education is a dry way of looking at it. Rather, our objective is to generate an interest in learning." says Swarup.

More info @
http://timesofindia.indiatimes.com/Lifes_lessons_learnt_on_the_sidewalk/articleshow/2039449.cms

The Muppet Movie

Memorable quote (s) from the movie:

Fozzie (Frank Oz): You can come with us.

Gonzo Dave Goelz): Where are you going?

Fozzie (Frank Oz): We're following our dreams!

Gonzo (Dave Goelz): Really? I have a dream, too.

Fozzie (Frank Oz): What?

Gonzo (Dave Goelz): You might think it's stupid.

Fozzie (Frank Oz): No.

Gonzo (Dave Goelz): Well, I want to go to Bombay, India to become a movie star.

Fozzie (Frank Oz): You don't go to Bombay to become a movie star. You go where we're going, Hollywood.

Gonzo (Dave Goelz): Well, sure, if you want to do it the easy way.

On The Future

Gabi Tolkowsky writes:

We’re in a time of big changes. There have been so many discoveries; we have to stop for reflection. There is a lack of young people cutting and there is a disappearance of master cutters, who are not being replaced fast enough. Times are not easy, so younger people are taking fewer risks. They don’t jump in without thinking about it first. But we will have new technology and marketing that will be available to a new generation.