Wednesday, May 23, 2007
Mexican Turquoise
It has been reported that new production of turquoise from a large open-pit copper mine, about 110 km south of the U.S border from Douglas, Arizona is the new source. The Nacozari turquoise is found in nodules; though chalky much of the material is hard enough with good color. The rough pieces show inclusions of pyrite, quartz, and mica. Most materials are fashioned as cabochon or free form. The materials may be stabilized to improve color.
Burmese Pezzottaite
It has been reported that after Madagascar and Afghanistan, Khatchel, near Molo, in the Momeik area of Burma's Mogok district is the new source for pezzottaite. The crystals are tabular with colors ranging from pinkish orange to purplish pink.
Andes Jade
Andes Jade is the marketing name for serpentinite from central-western Argentina. The material is translucent to opaque with colors ranging from light to dark green, to bluish green to black. Analytical tests indicate a mixture of antigorite and lizardite with magnesite and magnetite. Some specimens are magnetic. The material is used for carvings; good ones may be cut as cabochons.
How Color Names Developed
Here is an interesting concept on color communication for colored stone dealers, gemologists, jewelers and consumers alike.
Methuen writes:
The purpose of a color name is to communicate the appearance of a given color or to enable us to think in color. Thus the color name must be so characteristic of the color’s appearance that it is readily understood by others. Since our environment is the source of colors, it is here that we must look for objects of typical colors, objects for which we already have names and which can be used to designate a characteristic appearance. Such was the case with the words blood and red, the oldest color name found in most languages. White and black are also of ancient origin and often derived from the concepts of light and dark symbolized by day and night. From the Sanskrit candra (light) came the Latin candidus (white). The Russian belyi (white) is derived from the root bhe (to lighten). The English white is derived from the Germanic xwitaz, which is related to the Russian svet (light). Similarly, black and dark share common origins. The German Schwarz (black) is related to the Nordic sortna (to darken), the Latin suasum (a dark place), and the archaic English swart, which means darkness and black (hence swarthy).
The word for yellow is also of early origin in many languages, usually derived from the names for fruits, straw, gold, fire or bile (the German galle, the Italian giallo). The words for green and blue developed at a later date, perhaps because the materials necessary to form these pigments were not as readily available. Green is naturally related to the phenomenon of growth and greenery. Blue, strangely enough, is often derived from the word for pale or yellow, perhaps because the sky often is a pale blue or even yellowish.
Among the oldest color names, those for red, yellow, green, blue, white, black, correspond with the basic concepts discussed previously. Here we shall describe these as basic names of the first order. Names of the second order are words such as beige, blonde, grey, brown, golden, lilac, magenta, olive, orange, pale, purple, rose, ruby, turquoise and violet, that is, color names which are independent words and characterize more or less specific colors or color areas.
When basic color names are combined with one another, they designate intermediate colors such as yellow green, blue black, golden blonde. The basic color names and their combinations will be grouped together under the term general color names. As the need for more refined color descriptions arose, the general color names were varied by the addition of modifiers resulting in terms such as light blue, pastel green, deep black. The addition of suffixes, such as the ish in yellowish, can be useful in describing the changes which take place in a gradual color shift, for example: green, bluish green, blue green, green blue, greenish blue, blue.
Another, larger group of color names are directly derived from specific elements in our environment. In addition to the words for the specific elements or objects which identify colors, the terms in this group usually include a basic color name. Below are some examples of color names which belong to this group:
1. Color names derived from plants: apricot (yellow), lemon yellow, grass green, hazel, rose red.
2. Color names derived from minerals and metals: alabaster, amethyst (violet), copper (red), malachite green, platinum blonde, turquoise blue.
3. Color names derived from man-made products: chocolate (brown), faience blue, bottle green, wine red.
4. Color names derived from fauna: beaver, canary yellow, mouse grey, fox, butterfly blue.
5. Color names derived from geographic names: Berlin blue, Copenhagen blue, Naples yellow, Pompeian red, Spanish green.
6. Color names derived from natural phenomena: aurora, spring green, sky blue, fire red, fog.
7. Color names derived from miscellaneous subjects: calypso (red), infra-red.
The importance of the basic color names and particularly those of the first order is evident from the frequency with which they occur in color descriptions. About one half of color descriptions contain a basic name of the first order and about one quarter a secondary basic name; in addition, combinations of both occupy about one sixth of such descriptions.
Thus far we have considered color names of one or two words, for example, blue, yellow grey, light red, deep black (yellow plus grey, light plus red, deep plus black). Color names with three or more parts are impractical. Four-part names such as light blue green grey are exceedingly difficult to visualize; even a three-part name such as grey brown red can prove awkward in usage.
In everyday speech, however, we often use auxiliary words before the proper color name; for example, a radiant orange red, a strong blue violet, a dark blue green, a warm red brown. These auxiliary words specify a slight variation of the color name proper. With time, part of the color name proper may itself become an auxiliary word; the name grey violet, for example, became more commonly known as grayish violet, and blue green also became known as bluish green. There are too many auxiliary words, such a strong and deep, to include in the dictionary. If well chosen, however, their meaning can be easily understood.
The method of forming color names outlined here obviously permits the formation of an almost unlimited number of color names, many of which would prove superfluous. Although such a flood of names is impractical, constantly changing fashions demand an ever increasing variety of color names—often in such fantastic combinations that a name becomes vague or meaningless; when it does have a meaning, this may change from year to year.
Methuen writes:
The purpose of a color name is to communicate the appearance of a given color or to enable us to think in color. Thus the color name must be so characteristic of the color’s appearance that it is readily understood by others. Since our environment is the source of colors, it is here that we must look for objects of typical colors, objects for which we already have names and which can be used to designate a characteristic appearance. Such was the case with the words blood and red, the oldest color name found in most languages. White and black are also of ancient origin and often derived from the concepts of light and dark symbolized by day and night. From the Sanskrit candra (light) came the Latin candidus (white). The Russian belyi (white) is derived from the root bhe (to lighten). The English white is derived from the Germanic xwitaz, which is related to the Russian svet (light). Similarly, black and dark share common origins. The German Schwarz (black) is related to the Nordic sortna (to darken), the Latin suasum (a dark place), and the archaic English swart, which means darkness and black (hence swarthy).
The word for yellow is also of early origin in many languages, usually derived from the names for fruits, straw, gold, fire or bile (the German galle, the Italian giallo). The words for green and blue developed at a later date, perhaps because the materials necessary to form these pigments were not as readily available. Green is naturally related to the phenomenon of growth and greenery. Blue, strangely enough, is often derived from the word for pale or yellow, perhaps because the sky often is a pale blue or even yellowish.
Among the oldest color names, those for red, yellow, green, blue, white, black, correspond with the basic concepts discussed previously. Here we shall describe these as basic names of the first order. Names of the second order are words such as beige, blonde, grey, brown, golden, lilac, magenta, olive, orange, pale, purple, rose, ruby, turquoise and violet, that is, color names which are independent words and characterize more or less specific colors or color areas.
When basic color names are combined with one another, they designate intermediate colors such as yellow green, blue black, golden blonde. The basic color names and their combinations will be grouped together under the term general color names. As the need for more refined color descriptions arose, the general color names were varied by the addition of modifiers resulting in terms such as light blue, pastel green, deep black. The addition of suffixes, such as the ish in yellowish, can be useful in describing the changes which take place in a gradual color shift, for example: green, bluish green, blue green, green blue, greenish blue, blue.
Another, larger group of color names are directly derived from specific elements in our environment. In addition to the words for the specific elements or objects which identify colors, the terms in this group usually include a basic color name. Below are some examples of color names which belong to this group:
1. Color names derived from plants: apricot (yellow), lemon yellow, grass green, hazel, rose red.
2. Color names derived from minerals and metals: alabaster, amethyst (violet), copper (red), malachite green, platinum blonde, turquoise blue.
3. Color names derived from man-made products: chocolate (brown), faience blue, bottle green, wine red.
4. Color names derived from fauna: beaver, canary yellow, mouse grey, fox, butterfly blue.
5. Color names derived from geographic names: Berlin blue, Copenhagen blue, Naples yellow, Pompeian red, Spanish green.
6. Color names derived from natural phenomena: aurora, spring green, sky blue, fire red, fog.
7. Color names derived from miscellaneous subjects: calypso (red), infra-red.
The importance of the basic color names and particularly those of the first order is evident from the frequency with which they occur in color descriptions. About one half of color descriptions contain a basic name of the first order and about one quarter a secondary basic name; in addition, combinations of both occupy about one sixth of such descriptions.
Thus far we have considered color names of one or two words, for example, blue, yellow grey, light red, deep black (yellow plus grey, light plus red, deep plus black). Color names with three or more parts are impractical. Four-part names such as light blue green grey are exceedingly difficult to visualize; even a three-part name such as grey brown red can prove awkward in usage.
In everyday speech, however, we often use auxiliary words before the proper color name; for example, a radiant orange red, a strong blue violet, a dark blue green, a warm red brown. These auxiliary words specify a slight variation of the color name proper. With time, part of the color name proper may itself become an auxiliary word; the name grey violet, for example, became more commonly known as grayish violet, and blue green also became known as bluish green. There are too many auxiliary words, such a strong and deep, to include in the dictionary. If well chosen, however, their meaning can be easily understood.
The method of forming color names outlined here obviously permits the formation of an almost unlimited number of color names, many of which would prove superfluous. Although such a flood of names is impractical, constantly changing fashions demand an ever increasing variety of color names—often in such fantastic combinations that a name becomes vague or meaningless; when it does have a meaning, this may change from year to year.
Tuesday, May 22, 2007
World's Best Presentation Contest Winners
Slideshare.net announced the winners of the World's Best Presentation Contest:
Winners (chose by judges)
1. ShiftHappens by Jbrenman
2. Meet Henry by Chereemoore
3. Sustainable Food Lab by Chrislandry
People’s Choice Winners
1. PaniPuri--An Introduction by Thakkar
2. ShiftHappens by Jbrenman
3. Meet Henry by Chereeemoore
Tips for good presentation:
1. Big Fonts
2. Big Graphics
3. Good Story
Winners (chose by judges)
1. ShiftHappens by Jbrenman
2. Meet Henry by Chereemoore
3. Sustainable Food Lab by Chrislandry
People’s Choice Winners
1. PaniPuri--An Introduction by Thakkar
2. ShiftHappens by Jbrenman
3. Meet Henry by Chereeemoore
Tips for good presentation:
1. Big Fonts
2. Big Graphics
3. Good Story
The Trapiche Growth Phenomenon
There are various interpretations on the trapiche growth phenomena in colored stones. In the past experts got confused with the unusual growth pattern to twinning. The unusual growth pattern is usually visible in beryl, variety emerald, (Muzo, La Pena, Coscuez) and corundum, variety ruby and sapphire (Burma(Mong Hsu) and Vietnam). One theory is that the phenomenon in beryl and corundum are due to skeletal or dendritic growth, where edges and corners tend to grow much faster than the faces of a crystal. Another interpretation on the phenomenon in trapiche rubies and sapphires from Burma and Vietnam are due to skeletal growth followed by layer-by-layer growth. To make a long story short, rapid growth and changes in the growth conditions are believed to be the origin of the unusual patterns in beryl and corundum. The trapiche phenomenon is also seen in andalusite, tourmaline, and quartz. For now there are no nomenclatures for fixed star patterns that are being offered as trapiche in the gem market.
A Question Of Origin: A Different View
(via Gemological Digest, Vol.3, No.1, 1990) Charles A Schiffman writes:
Relating a source to the presence of certain inclusions or other physical properties is not a recent idea, but goes back to the last century. A good example in the literature is found in Max Bauer’s Edelsteinkunde, 3rd edition, Tauchnitz Verlag, 1896/1932; the author points out the great importance of inclusions in determining origins (page 499) and goes on about their description.
In more recent times, in the Handbook Of Gem Identification by R.T.Liddicoat, 11th edition, GIA, 1981, typical inclusions related to sources are quoted (pages 88-89, 95-96).
Inclusions As A Means Of Gemstone Identification by E.Gubelin, GIA, 1953, has been the standard course book at the GIA on the matter of inclusions related to source.
That gemstones of certain sources were highly favored long ago is a historical fact, independent from gemology.
This writer recalls one merchant who was proud because he dealt only in Burma rubies that he bought directly from Burma, following requests from customers in the jewelry trade, and he was not an isolated case.
The trade has a strong demand for origins that is documented by the Definitions of the CIBJO (published about 1968) in Europe, a body grouping a majority of dealers and retailers. The following is extracted from CIBJO:
Art.2: Designation of color and place of origin (a) names of gem localities used heretofore to describe the color of gemstones, cannot be used any longer (b) indications of place of origin can be only added if the origin is known and can actually be corroborated. This proof may be given either by physical properties, or by the stone’s inclusions, in so far as they are characteristic of a definite area.
Obviously there are limitations to finding out origins, i.e the absence of characteristic features. For this reason, the origin of many specimens of such gemstones as garnet, tourmaline and quart cannot be found.
An interesting point is that considering these limitations, where no origin may be objectively ascertained, a lab sometimes faces little understanding in trade circles.
Answering the demand from the market for general testing and for determination of origin, Gubelin Laboratory extended its activities (previously only for the company’s own needs) to outside inquiries in the late 1960’s.
Time has not stood still since then. Investigation has become a challenge to go beyond routine methods, using more complex instrumentation. Even so, some limitations will remain in the feasibility of this complex and difficult task, in an effort to base it on objective methods.
On the other side, the gemologist familiar with this field is conscious of the big commercial assets involved by people chasing the rare and exceptional items. This attitude is a very human one, so that it is hard to believe that interested parties will just forget about demanding origin information.
Showing different aspect of the question in this magazine will hopefully lead to a better understanding of the parties concerned, to improve their cooperation and contribute to solving pending questions.
Relating a source to the presence of certain inclusions or other physical properties is not a recent idea, but goes back to the last century. A good example in the literature is found in Max Bauer’s Edelsteinkunde, 3rd edition, Tauchnitz Verlag, 1896/1932; the author points out the great importance of inclusions in determining origins (page 499) and goes on about their description.
In more recent times, in the Handbook Of Gem Identification by R.T.Liddicoat, 11th edition, GIA, 1981, typical inclusions related to sources are quoted (pages 88-89, 95-96).
Inclusions As A Means Of Gemstone Identification by E.Gubelin, GIA, 1953, has been the standard course book at the GIA on the matter of inclusions related to source.
That gemstones of certain sources were highly favored long ago is a historical fact, independent from gemology.
This writer recalls one merchant who was proud because he dealt only in Burma rubies that he bought directly from Burma, following requests from customers in the jewelry trade, and he was not an isolated case.
The trade has a strong demand for origins that is documented by the Definitions of the CIBJO (published about 1968) in Europe, a body grouping a majority of dealers and retailers. The following is extracted from CIBJO:
Art.2: Designation of color and place of origin (a) names of gem localities used heretofore to describe the color of gemstones, cannot be used any longer (b) indications of place of origin can be only added if the origin is known and can actually be corroborated. This proof may be given either by physical properties, or by the stone’s inclusions, in so far as they are characteristic of a definite area.
Obviously there are limitations to finding out origins, i.e the absence of characteristic features. For this reason, the origin of many specimens of such gemstones as garnet, tourmaline and quart cannot be found.
An interesting point is that considering these limitations, where no origin may be objectively ascertained, a lab sometimes faces little understanding in trade circles.
Answering the demand from the market for general testing and for determination of origin, Gubelin Laboratory extended its activities (previously only for the company’s own needs) to outside inquiries in the late 1960’s.
Time has not stood still since then. Investigation has become a challenge to go beyond routine methods, using more complex instrumentation. Even so, some limitations will remain in the feasibility of this complex and difficult task, in an effort to base it on objective methods.
On the other side, the gemologist familiar with this field is conscious of the big commercial assets involved by people chasing the rare and exceptional items. This attitude is a very human one, so that it is hard to believe that interested parties will just forget about demanding origin information.
Showing different aspect of the question in this magazine will hopefully lead to a better understanding of the parties concerned, to improve their cooperation and contribute to solving pending questions.
When And Where Color Names Developed
Here is an interesting overview on the origin of color for the colored stone dealers, jewelers, gemologists and consumers.
Methuen writes:
Near the medieval village of Santillana del Mar in Northern Spain are the caves of Altamira, which contain some of the world’s most famous pre-historic paintings. In the flickering yellow light of a torch, cavemen saw bison, wild pigs, deer and horses painted on the cave walls in strong red earth, black and yellow ochre. The Cromagnon artist who painted these animals some 20000 years ago captured their movement with astonishing realism. In Lascaux and many other pre-historic caves, paintings of animals, rendered in similar colors and with equal artistry, have also been discovered.
The use of colors, however, extends even farther back in time, perhaps as much as 150,000 to 200,000 years. Ice age man buried his dead in red ochre or painted their bones a red color, he had observed that the flow of red blood meant the difference between life and death and probably believed that the color red itself was therefore life-giving.
The ability of Ice Age man to distinguish colors as existing independently of objects meant that the art of color abstraction had already been born. With its development arose the need for color names to identify these new concepts. To begin with, colors were probably given the same names as the paints, obtained from blood or ochre, which were used to produce them. In the oldest Indo-European language, Sanskrit, rudhira means blood; the first part of this word appears again in the Greek and Latin words for red (erythros and rutilus), as well as in the word red in many modern languages, such as the German rot, the Danish rod. Even the Eskimo word for red, aupaluktak, is derived from the word for blood, auk.
Man was probably long aware of the beauty inherent in the colors of his natural surroundings—the blue of the sky, the radiant orange and red hues of a sunset, the variety of colors found in flowers. But he probably was not aware of color as an independent concept until the idea of color assumed tangible form in its use for decorative or religious purposes. Since the concept of color as an independent entity is assumed to precede color names, the availability of materials which could be used as pigments was a prerequisite for the development of such names. A study of many cultures through the ages reveals that the use of an increasing variety of colors is accompanied by the development of words to characterize them.
The cave paintings described were rendered in only five colors: yellow, orange, red, brown and black. It is not until about 4500 B.C that we first find evidence of the use of blue (in the so-called Halaf culture in Mesopotamia). In Egypt, malachite green was used as a pigment in cosmetics before the era of the dynasties. In the Egypt and Babylonia of 4000 B.C we find an increasing number of colors used in ceramics, architecture, paintings and sculpture. Around 3000-2500 B.C, the Sumarians established a culture in Babylonia that evidenced a wealth of colors. There, the splendid blue stone, lapis lazuli, as well as other minerals and precious stones, were used for ornamental purpose. The Phoenicians discovered the color purple, which they made from a kind of whelk, and used to dye their clothes. The Egyptians introduced the use of blue purple and violet.
The knowledge and use of color traveled across Crete to Greece around 1600-1400 B.C. The use of contrasting combinations, such as yellow and light blue or red and blue, appears in the Golden Age of Greek culture between 600-400 B.C. The art of mixing colors to form new variations had long since been learned and the literature of the time offers a considerable selection of color names. When adopted by the Romans, these names formed the basis of the development of color names in most European languages.
Methuen writes:
Near the medieval village of Santillana del Mar in Northern Spain are the caves of Altamira, which contain some of the world’s most famous pre-historic paintings. In the flickering yellow light of a torch, cavemen saw bison, wild pigs, deer and horses painted on the cave walls in strong red earth, black and yellow ochre. The Cromagnon artist who painted these animals some 20000 years ago captured their movement with astonishing realism. In Lascaux and many other pre-historic caves, paintings of animals, rendered in similar colors and with equal artistry, have also been discovered.
The use of colors, however, extends even farther back in time, perhaps as much as 150,000 to 200,000 years. Ice age man buried his dead in red ochre or painted their bones a red color, he had observed that the flow of red blood meant the difference between life and death and probably believed that the color red itself was therefore life-giving.
The ability of Ice Age man to distinguish colors as existing independently of objects meant that the art of color abstraction had already been born. With its development arose the need for color names to identify these new concepts. To begin with, colors were probably given the same names as the paints, obtained from blood or ochre, which were used to produce them. In the oldest Indo-European language, Sanskrit, rudhira means blood; the first part of this word appears again in the Greek and Latin words for red (erythros and rutilus), as well as in the word red in many modern languages, such as the German rot, the Danish rod. Even the Eskimo word for red, aupaluktak, is derived from the word for blood, auk.
Man was probably long aware of the beauty inherent in the colors of his natural surroundings—the blue of the sky, the radiant orange and red hues of a sunset, the variety of colors found in flowers. But he probably was not aware of color as an independent concept until the idea of color assumed tangible form in its use for decorative or religious purposes. Since the concept of color as an independent entity is assumed to precede color names, the availability of materials which could be used as pigments was a prerequisite for the development of such names. A study of many cultures through the ages reveals that the use of an increasing variety of colors is accompanied by the development of words to characterize them.
The cave paintings described were rendered in only five colors: yellow, orange, red, brown and black. It is not until about 4500 B.C that we first find evidence of the use of blue (in the so-called Halaf culture in Mesopotamia). In Egypt, malachite green was used as a pigment in cosmetics before the era of the dynasties. In the Egypt and Babylonia of 4000 B.C we find an increasing number of colors used in ceramics, architecture, paintings and sculpture. Around 3000-2500 B.C, the Sumarians established a culture in Babylonia that evidenced a wealth of colors. There, the splendid blue stone, lapis lazuli, as well as other minerals and precious stones, were used for ornamental purpose. The Phoenicians discovered the color purple, which they made from a kind of whelk, and used to dye their clothes. The Egyptians introduced the use of blue purple and violet.
The knowledge and use of color traveled across Crete to Greece around 1600-1400 B.C. The use of contrasting combinations, such as yellow and light blue or red and blue, appears in the Golden Age of Greek culture between 600-400 B.C. The art of mixing colors to form new variations had long since been learned and the literature of the time offers a considerable selection of color names. When adopted by the Romans, these names formed the basis of the development of color names in most European languages.
Monday, May 21, 2007
Gem Mining And Sustainable Environmental Management in Sri Lanka
2007: How many dealers, jewelers and consumers actually know where the stones come from? Very few. Only a lucky few have had the opportunity to actually see the working of a mine. The island of Sri Lanka is blessed with virtually all known colored stones in the world, but most dealers, jewelers and consumers focus on high value stones and that's all they know. But the truth is otherwise; Sri Lanka is also a treasure trove for rare stones and the author explains in detail the mining methodology that is good for Sri Lanka with minimum environmental damage.
(via Journal of Gemmology, Vol.28, No.3, July 2002) P.G.R Dharmaratne writes:
Abstract
Various methods of accessing alluvial gem gravels (known as illama) in Sri Lanka for the extraction of gemstones, such as open pits, shafts and tunnels, and dredging, are briefly summarized. The methods adopted to minimize environmental damage caused by mining include: introduction of legislation, restriction on types of mining methods permitted, awareness programmes and restoration of mined-out lands. The lessons learned by the Sri Lankan gem industry, with centuries of experience, can be applied to other gem producing countries.
Introduction
Mining of minerals for the consumption by human beings started many centuries ago and if it were not for minerals and their products, the world would be without many of the material comforts for its population today. For example, life can not be imagined without having metal for machinery and motor vehicles, cement for construction, fuel and minerals for energy production, all of which are products of mining. Gems, though not an essential commodity, on the other hand make life more beautiful and attractive. So it can be said that minerals bring comforts for the body while gems give comfort for the senses and the eye in particular. Since minerals play such an important role in the lives of people, it is the duty of all of us to extract them with least possible damage to the environment in which we live.
Gem mining
Introduction
Sri Lanka has been identified as one of the earliest sources of gems in the world, and is still a leading producer. Mining activities were not properly organized until early 1970s; before 1970, gem mining was done haphazardly and different regulations were in force in different districts. With the establishment of the State Gem Corporation, predecessor to the National Gem and Jewellery Authority, in 1972 all the activities were brought under one institution and many regional offices were established to issue licenses for mining and thereby supervise and minimize the impact on the environment. One of the main objectives of the State Gem Corporation was the development, regulation and control of the gem industry. Mining increased rapidly with provision of many facilities to gem exporters. While legalized mining reduced the damage to the environment, illicit mining also continued and unlike licensed mining, this caused more extensive damage to the environment.
Mining by means of open pits
A gem bearing gravel bed occurring on or near the surface is exploited using mammoties and crowbars to excavate open pits most of which are without any support on their side walls. The miner fills bamboo baskets with grave, and throws them upward to the waiting hands of another man at the pit head. The method used for bailing out water from the pit depends on the rate of water seepage. It can be done by hand with buckets or by using mechanized water pumps. When the gem bearing gravel is reached, it is collected separately at the pit head, and washed in running water in closely woven conical bamboo baskets. If there is a shortage of water, material from surface digging can be dry sieved after removing the larger rocks by hand. Only the remaining material needs to be washed to remove dust and clay. With the correct techniques of washing, gemstones can be concentrated at the bottom of the sieve.
The use of bulldozers and scrapers has been allowed in special circumstances such as where very thin gem gravel beds occur, or in areas which have been mined out by open pits or shafts and tunnels. This machinery is used to remove the overburden, since open pit mining is no longer economical in such situations.
Mining by shafts and tunnels
The placer deposits of gems (illama) and in situ deposits occurring below a certain depth are mined by sinking shafts and excavating tunnels. In Sri Lanka, only placer deposits are mined by sinking pits, but for deeper deposits, recovery of the illama by successively deeper pits becomes uneconomical. In such situations, it is common practice to excavate horizontal tunnels at the level of the gem bearing gravel layer in order to recover gemstones. In small operations through hard ground, the shafts are either round (2m diameter) or square (2m sides), but in soft ground (e.g beneath paddy fields), they are rectangular in section, measuring about 2 x 4m.
The shaft is reinforced with timber crossbeams (from rubber trees0 while fern foliage is pushed between the sides of the shaft and vertical struts (arecanut trunks) are driven behind the crossbeams, to prevent the damp sidewalls from caving in. While shafts are 3-4m deep, clay and sand shoveled into small bamboo baskets are manually lifted up to the shaft head. Deeper shafts utilize manually operated winches to lift excavated material and water. As the rate of water flow increases, traditional methods of removing water are replaced by water pumps.
The illama is collected separately near the shaft at a place where the ground is specially leveled. The illama can be up to a few meters thick, and generally rests directly on decomposed rock (malawa) or unweathered rock (parugala). Washing the illama is done in a nearby stream or in a pond specially constructed for the purpose. The miners stand waist deep in the pond and move the baskets in a circular motion to remove all the lighter materials. Washing is continued for about half an hour with more illama being intermittently fed into the baskets. During the washing, lighter material collects at the top of the basket and is hand sorted and thrown out of the pond, while the heavy gem bearing material settles at the bottom of the basket. After washing, the baskets are stacked. Later, an experienced miner collects the gems while sweeping the gravel back and forth by hand.
When illama is at a fairly deep level (>8m) horizontal tunnels, 1-2m high, are excavated from the bottom of the shaft so that the floor of the tunnel follows or lies on the rock layer underlying the illama. As the tunnels are excavated deeper into the surrounding area, an adequate supply of fresh air and oxygen for breathing as well as for lighting candles, becomes more difficult. In such situations, air pumps are installed to provide fresh air into the mine. The tunnels are supported with timber and crossbeams similar to those of the main shaft. In Sri Lanka, over 60 percent of the mining is done by shafts and tunnels.
River dredging
When the gem bearing placer deposits occur at the bottom of a shallow river, long-handled mammoties (a type of manual scraper with the blade perpendicular to the handle so that material can be scooped up towards the user) are used to scoop up the gravel. To prepare for this process, a brushwood dam is erected at a place where the river slows down naturally, and the water is allowed to escape from one side of the dam. Using long-handled mammoties, the overlying sand and gravel are scooped over the place where water passes through. This procedure is continued until the illama is reached. The illama is then loosened by using long pointed steel rods and is also scooped into the moving water which removes the lighter and finer minerals, leaving heavy gem minerals behind. Good gemstones can be easily seen and hand picked and the rest of the gravel is washed in the same manner as discussed earlier.
In the past, gravel pumps and dredgers could be used to extract the overburden and gem gravel, but they are banned at present because of the damage they cause to river banks.
Environmental management
Causes of environmental damage
Damage to the environment due to gem mining has been discussed by de Silva (1989), Rupasinghe and Cooray (1993) and Dharmaratne (1994).
1. Damage to land and vegetation cover
Most damage to land caused by mining activities is due to open-pit methods. In particular, mining for topaz involves large volumes of earth to recover gemstones. Illicit miners leave behind larger craters and pits, particularly in the forests, which fill with water and become breeding grounds for mosquitoes; this in turn endangers the lives of people and animals.
Tree trunks are used to support the walls and roofs of shafts and tunnels and the flow of earth into the workings is prevented by lagging with variety of fern (kekilla). This fern has strong roots which bind the soil and prevent soil erosion. Large areas of fern cover are harvested annually to support many thousands of gem pits, and consequently, during the monsoon rains heavy erosion occurs in these areas.
2. Damage to plantations
When near-surface gem deposits are discovered in plantations of tea, rubber, coconut or pepper, mining is carried out without any consideration or respect for the trees. Valuable trees are either removed deliberately or fall down due to excavation. The loss of good plantations, damages the national economy.
3. Damage to rivers and river banks
Gem mining in rivers and streams is allowed by the NGJA only because of the uncontrollable nature of illicit mining. Illicit miners not only dredge the river bottom but also damage river banks by undercutting. Their operations may take place by day and by night. During dredging, fine clay particles can be released into suspension in the water and cause the death of river species; they can also prevent use of water for bathing and drinking. Furthermore, the sedimentation of waterways and dams reduces the efficiency of hydroelectric power plants.
4. Damage to buildings and properties
Tunneling under roads, buildings, canals, culverts and other structures can cause untold damage. There are many instances of land owners literally undermining their own properties, because it is sometimes worth the risk of forgoing a property in the hope of recovering high value gemstones.
Legislature
The State Gem Corporation Act No.13 of 1971 was repealed in 1993 and the National Gem and Jewellery Authority Act No.50 of 1993 came into effect with regard to the gem and jewellery industry. The Act states that:
‘No person shall carry on the gem industry except under the authority of a license issued by the Authority and every person who commits an offence under this Act shall on conviction after a trial before a magistrate, be liable to a fine not exceeding one million rupees or to imprisonment for a period not exceeding five years or to both such fine and imprisonment.’
The NGJA can, with the consent of the relevant parties, having regard to the circumstances in which any offence under this act was committed, compound such offence for a sum of not exceeding one third the maximum fine imposable.
The regulations in respect of the gem and jewelry industry were gazetted in 1972. Accordingly a license for mining for gems is issued under the following conditions:
1. The land owner/co-owners should give consent in writing to the prospective license.
2. If the land in question is cultivated; the consent of the cultivator too should be obtained if he is not the owner of the land.
3. In the case of cultivated land the consent of the regional office of the Agrarian Services Department should be obtained and the ASD takes a security deposit for each pit to ensure that the license restores the land after mining. The NGJA also takes a security deposit for each pit to ensure that the pits are closed, as is the responsibility of the NGJA to restore lands after mining. In the case of river dredging, substantial security deposits are required by the NGJA for the possible work involved in much larger than that for restoration of mining damage on high ground.
4. In mining cultivated land and rivers, water pumps are the only machinery allowed. Backhoes are permitted only in special circumstances and only with a very large security deposit since the excavations created are much larger than in normal pit mining.
Control of illicit gem mining
Raids are conducted with the assistance of the police to enforce the regulations and to apprehend offenders, because sometimes illicit gem miners attack unarmed field officers. There have been occasions in the past when even armed police have been the victims of illicit gem miners who sometimes flock in their thousands to new gem deposits discovered near the surface. The police have the authority to conduct their own raids and on such occasions, offenders are brought before a court of justice and due punishments is given.
Illicit mining in State lands, rivers and roads, or their reservations, is treated very seriously and the punishments are high compared with those for illicit mining on private land. Roads, rivers and their reservations, which comprise about 10 meters one each side of the road or river, belong to the government, and construction or excavation is not allowed in the reservations in order to safeguard these routes. If, for example, a water pump is seized on private land, it may be released with a fine of Rs.2500, whereas if the same pump were seized in one of the above mentioned locations, the fine may be a third of the value of the pump if it is a first offence, two thirds of the value if the offence is repeated and on a third offence the pump is forfeited to the State. Water pumps are the most common machines used in gem mining, and although gravel pumps, bulldozers and scrapers are rarely used, they too can be seized if used illicitly. This practice has been in operation for many years. However it has now been found that it is not a sufficient deterrent and therefore action has been taken to increase the severity of the punishment and to seize the machinery on the first offence. This is done particularly to discourage the use of gravel pumps in rivers and bulldozers and scrapers in large scale excavations in illicit mines.
Restoration of mined out lands
The security deposits kept at the NGJA are released only if the pits are closed and the lands are restored in a fit state for cultivation. Most often, when the value of gemstones found is very high, miners ignore the need to close pits and reclaim the land. The NGJA has established a rehabilitation fund with the money from those unclaimed deposits. During the recent past this fund has financed the following activities:
1. Conducting seminars for the gem mining community to educate them in environmentally friendly mining methods and restoration of lands.
2. Restoration of river banks by erecting brushwood dams along the original river boundary and filling the excavated area behind it; also planting suitable trees along the river banks.
3. Restoration of mined-out land by using bulldozers and scrapers and planting trees.
Conclusions
Mining by any method and for any mineral cause environmental damage and the only action that can be taken is to ensure that the damage is minimized. In the case of gem mining in Sri Lanka, many hundreds of thousands of people are engaged in gem mining, with or without a license from the NGJA. While the damage to the environment by legalized mining is minimal, the greatest harm comes from illicit mining and results in unfilled pits, soil heaps and pollution of waterways.
Illicit gem mining is not a problem specific to Sri Lanka, but faced by all gem producing countries. The discoveries of near surface deposits have caused gem rushes involving thousands of people in Sri Lanka, Madagascar, Tanzania, Brazil and in many other countries. Licensed mining can be supervised and strict rules can be enforced to reduce the environmental degradation. The field officers of the NGJA with the assistance of police make every effort to stop illicit mining, but the nature of such operations and the number of people involved prevents its complete eradication. The damage that illicit mining causes is offset to some extent by a rehabilitation fund established by the NGJA which is used to restore mined out lands.
(via Journal of Gemmology, Vol.28, No.3, July 2002) P.G.R Dharmaratne writes:
Abstract
Various methods of accessing alluvial gem gravels (known as illama) in Sri Lanka for the extraction of gemstones, such as open pits, shafts and tunnels, and dredging, are briefly summarized. The methods adopted to minimize environmental damage caused by mining include: introduction of legislation, restriction on types of mining methods permitted, awareness programmes and restoration of mined-out lands. The lessons learned by the Sri Lankan gem industry, with centuries of experience, can be applied to other gem producing countries.
Introduction
Mining of minerals for the consumption by human beings started many centuries ago and if it were not for minerals and their products, the world would be without many of the material comforts for its population today. For example, life can not be imagined without having metal for machinery and motor vehicles, cement for construction, fuel and minerals for energy production, all of which are products of mining. Gems, though not an essential commodity, on the other hand make life more beautiful and attractive. So it can be said that minerals bring comforts for the body while gems give comfort for the senses and the eye in particular. Since minerals play such an important role in the lives of people, it is the duty of all of us to extract them with least possible damage to the environment in which we live.
Gem mining
Introduction
Sri Lanka has been identified as one of the earliest sources of gems in the world, and is still a leading producer. Mining activities were not properly organized until early 1970s; before 1970, gem mining was done haphazardly and different regulations were in force in different districts. With the establishment of the State Gem Corporation, predecessor to the National Gem and Jewellery Authority, in 1972 all the activities were brought under one institution and many regional offices were established to issue licenses for mining and thereby supervise and minimize the impact on the environment. One of the main objectives of the State Gem Corporation was the development, regulation and control of the gem industry. Mining increased rapidly with provision of many facilities to gem exporters. While legalized mining reduced the damage to the environment, illicit mining also continued and unlike licensed mining, this caused more extensive damage to the environment.
Mining by means of open pits
A gem bearing gravel bed occurring on or near the surface is exploited using mammoties and crowbars to excavate open pits most of which are without any support on their side walls. The miner fills bamboo baskets with grave, and throws them upward to the waiting hands of another man at the pit head. The method used for bailing out water from the pit depends on the rate of water seepage. It can be done by hand with buckets or by using mechanized water pumps. When the gem bearing gravel is reached, it is collected separately at the pit head, and washed in running water in closely woven conical bamboo baskets. If there is a shortage of water, material from surface digging can be dry sieved after removing the larger rocks by hand. Only the remaining material needs to be washed to remove dust and clay. With the correct techniques of washing, gemstones can be concentrated at the bottom of the sieve.
The use of bulldozers and scrapers has been allowed in special circumstances such as where very thin gem gravel beds occur, or in areas which have been mined out by open pits or shafts and tunnels. This machinery is used to remove the overburden, since open pit mining is no longer economical in such situations.
Mining by shafts and tunnels
The placer deposits of gems (illama) and in situ deposits occurring below a certain depth are mined by sinking shafts and excavating tunnels. In Sri Lanka, only placer deposits are mined by sinking pits, but for deeper deposits, recovery of the illama by successively deeper pits becomes uneconomical. In such situations, it is common practice to excavate horizontal tunnels at the level of the gem bearing gravel layer in order to recover gemstones. In small operations through hard ground, the shafts are either round (2m diameter) or square (2m sides), but in soft ground (e.g beneath paddy fields), they are rectangular in section, measuring about 2 x 4m.
The shaft is reinforced with timber crossbeams (from rubber trees0 while fern foliage is pushed between the sides of the shaft and vertical struts (arecanut trunks) are driven behind the crossbeams, to prevent the damp sidewalls from caving in. While shafts are 3-4m deep, clay and sand shoveled into small bamboo baskets are manually lifted up to the shaft head. Deeper shafts utilize manually operated winches to lift excavated material and water. As the rate of water flow increases, traditional methods of removing water are replaced by water pumps.
The illama is collected separately near the shaft at a place where the ground is specially leveled. The illama can be up to a few meters thick, and generally rests directly on decomposed rock (malawa) or unweathered rock (parugala). Washing the illama is done in a nearby stream or in a pond specially constructed for the purpose. The miners stand waist deep in the pond and move the baskets in a circular motion to remove all the lighter materials. Washing is continued for about half an hour with more illama being intermittently fed into the baskets. During the washing, lighter material collects at the top of the basket and is hand sorted and thrown out of the pond, while the heavy gem bearing material settles at the bottom of the basket. After washing, the baskets are stacked. Later, an experienced miner collects the gems while sweeping the gravel back and forth by hand.
When illama is at a fairly deep level (>8m) horizontal tunnels, 1-2m high, are excavated from the bottom of the shaft so that the floor of the tunnel follows or lies on the rock layer underlying the illama. As the tunnels are excavated deeper into the surrounding area, an adequate supply of fresh air and oxygen for breathing as well as for lighting candles, becomes more difficult. In such situations, air pumps are installed to provide fresh air into the mine. The tunnels are supported with timber and crossbeams similar to those of the main shaft. In Sri Lanka, over 60 percent of the mining is done by shafts and tunnels.
River dredging
When the gem bearing placer deposits occur at the bottom of a shallow river, long-handled mammoties (a type of manual scraper with the blade perpendicular to the handle so that material can be scooped up towards the user) are used to scoop up the gravel. To prepare for this process, a brushwood dam is erected at a place where the river slows down naturally, and the water is allowed to escape from one side of the dam. Using long-handled mammoties, the overlying sand and gravel are scooped over the place where water passes through. This procedure is continued until the illama is reached. The illama is then loosened by using long pointed steel rods and is also scooped into the moving water which removes the lighter and finer minerals, leaving heavy gem minerals behind. Good gemstones can be easily seen and hand picked and the rest of the gravel is washed in the same manner as discussed earlier.
In the past, gravel pumps and dredgers could be used to extract the overburden and gem gravel, but they are banned at present because of the damage they cause to river banks.
Environmental management
Causes of environmental damage
Damage to the environment due to gem mining has been discussed by de Silva (1989), Rupasinghe and Cooray (1993) and Dharmaratne (1994).
1. Damage to land and vegetation cover
Most damage to land caused by mining activities is due to open-pit methods. In particular, mining for topaz involves large volumes of earth to recover gemstones. Illicit miners leave behind larger craters and pits, particularly in the forests, which fill with water and become breeding grounds for mosquitoes; this in turn endangers the lives of people and animals.
Tree trunks are used to support the walls and roofs of shafts and tunnels and the flow of earth into the workings is prevented by lagging with variety of fern (kekilla). This fern has strong roots which bind the soil and prevent soil erosion. Large areas of fern cover are harvested annually to support many thousands of gem pits, and consequently, during the monsoon rains heavy erosion occurs in these areas.
2. Damage to plantations
When near-surface gem deposits are discovered in plantations of tea, rubber, coconut or pepper, mining is carried out without any consideration or respect for the trees. Valuable trees are either removed deliberately or fall down due to excavation. The loss of good plantations, damages the national economy.
3. Damage to rivers and river banks
Gem mining in rivers and streams is allowed by the NGJA only because of the uncontrollable nature of illicit mining. Illicit miners not only dredge the river bottom but also damage river banks by undercutting. Their operations may take place by day and by night. During dredging, fine clay particles can be released into suspension in the water and cause the death of river species; they can also prevent use of water for bathing and drinking. Furthermore, the sedimentation of waterways and dams reduces the efficiency of hydroelectric power plants.
4. Damage to buildings and properties
Tunneling under roads, buildings, canals, culverts and other structures can cause untold damage. There are many instances of land owners literally undermining their own properties, because it is sometimes worth the risk of forgoing a property in the hope of recovering high value gemstones.
Legislature
The State Gem Corporation Act No.13 of 1971 was repealed in 1993 and the National Gem and Jewellery Authority Act No.50 of 1993 came into effect with regard to the gem and jewellery industry. The Act states that:
‘No person shall carry on the gem industry except under the authority of a license issued by the Authority and every person who commits an offence under this Act shall on conviction after a trial before a magistrate, be liable to a fine not exceeding one million rupees or to imprisonment for a period not exceeding five years or to both such fine and imprisonment.’
The NGJA can, with the consent of the relevant parties, having regard to the circumstances in which any offence under this act was committed, compound such offence for a sum of not exceeding one third the maximum fine imposable.
The regulations in respect of the gem and jewelry industry were gazetted in 1972. Accordingly a license for mining for gems is issued under the following conditions:
1. The land owner/co-owners should give consent in writing to the prospective license.
2. If the land in question is cultivated; the consent of the cultivator too should be obtained if he is not the owner of the land.
3. In the case of cultivated land the consent of the regional office of the Agrarian Services Department should be obtained and the ASD takes a security deposit for each pit to ensure that the license restores the land after mining. The NGJA also takes a security deposit for each pit to ensure that the pits are closed, as is the responsibility of the NGJA to restore lands after mining. In the case of river dredging, substantial security deposits are required by the NGJA for the possible work involved in much larger than that for restoration of mining damage on high ground.
4. In mining cultivated land and rivers, water pumps are the only machinery allowed. Backhoes are permitted only in special circumstances and only with a very large security deposit since the excavations created are much larger than in normal pit mining.
Control of illicit gem mining
Raids are conducted with the assistance of the police to enforce the regulations and to apprehend offenders, because sometimes illicit gem miners attack unarmed field officers. There have been occasions in the past when even armed police have been the victims of illicit gem miners who sometimes flock in their thousands to new gem deposits discovered near the surface. The police have the authority to conduct their own raids and on such occasions, offenders are brought before a court of justice and due punishments is given.
Illicit mining in State lands, rivers and roads, or their reservations, is treated very seriously and the punishments are high compared with those for illicit mining on private land. Roads, rivers and their reservations, which comprise about 10 meters one each side of the road or river, belong to the government, and construction or excavation is not allowed in the reservations in order to safeguard these routes. If, for example, a water pump is seized on private land, it may be released with a fine of Rs.2500, whereas if the same pump were seized in one of the above mentioned locations, the fine may be a third of the value of the pump if it is a first offence, two thirds of the value if the offence is repeated and on a third offence the pump is forfeited to the State. Water pumps are the most common machines used in gem mining, and although gravel pumps, bulldozers and scrapers are rarely used, they too can be seized if used illicitly. This practice has been in operation for many years. However it has now been found that it is not a sufficient deterrent and therefore action has been taken to increase the severity of the punishment and to seize the machinery on the first offence. This is done particularly to discourage the use of gravel pumps in rivers and bulldozers and scrapers in large scale excavations in illicit mines.
Restoration of mined out lands
The security deposits kept at the NGJA are released only if the pits are closed and the lands are restored in a fit state for cultivation. Most often, when the value of gemstones found is very high, miners ignore the need to close pits and reclaim the land. The NGJA has established a rehabilitation fund with the money from those unclaimed deposits. During the recent past this fund has financed the following activities:
1. Conducting seminars for the gem mining community to educate them in environmentally friendly mining methods and restoration of lands.
2. Restoration of river banks by erecting brushwood dams along the original river boundary and filling the excavated area behind it; also planting suitable trees along the river banks.
3. Restoration of mined-out land by using bulldozers and scrapers and planting trees.
Conclusions
Mining by any method and for any mineral cause environmental damage and the only action that can be taken is to ensure that the damage is minimized. In the case of gem mining in Sri Lanka, many hundreds of thousands of people are engaged in gem mining, with or without a license from the NGJA. While the damage to the environment by legalized mining is minimal, the greatest harm comes from illicit mining and results in unfilled pits, soil heaps and pollution of waterways.
Illicit gem mining is not a problem specific to Sri Lanka, but faced by all gem producing countries. The discoveries of near surface deposits have caused gem rushes involving thousands of people in Sri Lanka, Madagascar, Tanzania, Brazil and in many other countries. Licensed mining can be supervised and strict rules can be enforced to reduce the environmental degradation. The field officers of the NGJA with the assistance of police make every effort to stop illicit mining, but the nature of such operations and the number of people involved prevents its complete eradication. The damage that illicit mining causes is offset to some extent by a rehabilitation fund established by the NGJA which is used to restore mined out lands.
A Question Of Origin: A Different View
2007: Here is an interesting perspective on the question of origin from the father of inclusion studies.
(via Gemological Digest, Vol.3, No.1, 1990) Dr Eduard Gubelin writes:
The pros and cons of origin reports have been discussed on so many occasions during numerous conferences that I do not wish to repeat the arguments. Yet my strongest arguments in favor of origin reports are:
a) The fact that gemstones are very valuable and rare objects, and as such are entitled to be compared with objects of art and antiquity. It is customary that art and antique collectors request and receive a certificate of origin and authenticity. I see no reason why buyers of gemstones should not have the same right to ask for and obtain a certificate of origin and genuineness. The request for a certificate of origin need not necessarily be limited to the few precious gemstones (alexandrite, emerald, diamond, black opal, ruby and sapphire) but could be extended to the less expensive gemstones (beryls, chrysoberyls, peridot, quartz, topaz, tourmaline, spinel, etc). I have the feeling that my quite representative and comprehensive gem collection has been admired by all those prominent gemologists who have seen it because each individual specimen is marked with its origin. Why shouldn’t other buyers and collectors of gemstones be entitled to know the origin of their collector’s items? You know just as well I do that gemstones are among the items least commonly collected. Definitely much less than paintings, antiques, weapons, stamps or even such odd objects as hats, scarves and uniform buttons. Personally I am convinced that origin reports honestly and correctly stated would help a great deal to stimulate many more people to collect gemstones.
(b) My next argument in favor of origin reports is scientific: Of what value are the more recent and very profound investigations of, and publications on, original gem deposits such as those by Dr Hanni (about the emerald mines at Santa Terezinha da Goias, the emerald mine of Belmont near Itabira or the emerald deposit of Ankadilalana on Madagascar), or Dr Peter Keller’s research (on rubies from Mogok and those from Thailand), or my studies (of gem deposits of Sri Lanka, at Mogok, the jade occurrences in Northern Burma, and the gem deposits in Pakistan, and so son and so forth), if afterwards neither the authors of these studies nor other learned gemologists are allowed to profit from their intrinsic knowledge and experience? After all, the details in these very valuable articles about old and new gem deposits serve the purpose that gemstones occurring in the described deposits may be recognized as such by their particularities of origin. Thanks to Dr Hanni’ publications about emeralds from Santa Terezinha and those from Belmont, numerous interested gemologists are definitely capable of recognizing and distinguishing the emeralds from these two sources at first sight without any difficulty, and even discerning them from those originating, for instance, from Chivor or the Muzo area. Without bragging, I may emphasize that the staff of the Gubelin Laboratory under the directorship of Mr C A Schiffmann, as well myself, could very easily undertake such a distinction under the condition that the gemological properties agree with one or other of these well-known emerald deposits.
Your argument concerning the uranium pyrochlore inclusions in Pailin sapphires which have also been observed in Australian sapphires may seem to be correct, but it is not quite so, because in any scientific work, progress and new observations are made. Yet whenever a publication is made, the author can only state his knowledge at the time of writing. It is not his mistake if later on new discoveries are made, but he must be ready to correct his previously made incomplete or incorrect statement. Mr John Koivula did so in the Photoatlas of Inclusions In Gemstones. As a matter of fact, the text had already been typed when I learned that pyrochlore is also present in Australian sapphires. Consequently I not only corrected this statement, but presented further detailed knowledge by stating that urnanium pyrochlore is a frequent guest mineral in sapphires originating from a basaltic environment. Perhaps these arguments may enrich the discussion about this problem of origin reports.
(via Gemological Digest, Vol.3, No.1, 1990) Dr Eduard Gubelin writes:
The pros and cons of origin reports have been discussed on so many occasions during numerous conferences that I do not wish to repeat the arguments. Yet my strongest arguments in favor of origin reports are:
a) The fact that gemstones are very valuable and rare objects, and as such are entitled to be compared with objects of art and antiquity. It is customary that art and antique collectors request and receive a certificate of origin and authenticity. I see no reason why buyers of gemstones should not have the same right to ask for and obtain a certificate of origin and genuineness. The request for a certificate of origin need not necessarily be limited to the few precious gemstones (alexandrite, emerald, diamond, black opal, ruby and sapphire) but could be extended to the less expensive gemstones (beryls, chrysoberyls, peridot, quartz, topaz, tourmaline, spinel, etc). I have the feeling that my quite representative and comprehensive gem collection has been admired by all those prominent gemologists who have seen it because each individual specimen is marked with its origin. Why shouldn’t other buyers and collectors of gemstones be entitled to know the origin of their collector’s items? You know just as well I do that gemstones are among the items least commonly collected. Definitely much less than paintings, antiques, weapons, stamps or even such odd objects as hats, scarves and uniform buttons. Personally I am convinced that origin reports honestly and correctly stated would help a great deal to stimulate many more people to collect gemstones.
(b) My next argument in favor of origin reports is scientific: Of what value are the more recent and very profound investigations of, and publications on, original gem deposits such as those by Dr Hanni (about the emerald mines at Santa Terezinha da Goias, the emerald mine of Belmont near Itabira or the emerald deposit of Ankadilalana on Madagascar), or Dr Peter Keller’s research (on rubies from Mogok and those from Thailand), or my studies (of gem deposits of Sri Lanka, at Mogok, the jade occurrences in Northern Burma, and the gem deposits in Pakistan, and so son and so forth), if afterwards neither the authors of these studies nor other learned gemologists are allowed to profit from their intrinsic knowledge and experience? After all, the details in these very valuable articles about old and new gem deposits serve the purpose that gemstones occurring in the described deposits may be recognized as such by their particularities of origin. Thanks to Dr Hanni’ publications about emeralds from Santa Terezinha and those from Belmont, numerous interested gemologists are definitely capable of recognizing and distinguishing the emeralds from these two sources at first sight without any difficulty, and even discerning them from those originating, for instance, from Chivor or the Muzo area. Without bragging, I may emphasize that the staff of the Gubelin Laboratory under the directorship of Mr C A Schiffmann, as well myself, could very easily undertake such a distinction under the condition that the gemological properties agree with one or other of these well-known emerald deposits.
Your argument concerning the uranium pyrochlore inclusions in Pailin sapphires which have also been observed in Australian sapphires may seem to be correct, but it is not quite so, because in any scientific work, progress and new observations are made. Yet whenever a publication is made, the author can only state his knowledge at the time of writing. It is not his mistake if later on new discoveries are made, but he must be ready to correct his previously made incomplete or incorrect statement. Mr John Koivula did so in the Photoatlas of Inclusions In Gemstones. As a matter of fact, the text had already been typed when I learned that pyrochlore is also present in Australian sapphires. Consequently I not only corrected this statement, but presented further detailed knowledge by stating that urnanium pyrochlore is a frequent guest mineral in sapphires originating from a basaltic environment. Perhaps these arguments may enrich the discussion about this problem of origin reports.
Sunday, May 20, 2007
3 Lessons B-schools Miss Teaching
I wish the gemological schools taught the concepts as part of the program. Most gemologists who graduate lack soft skills and are unemployable for variety of reasons. Here is a thought-provoking article for self-examination.
Nalin Garg writes:
Business schools are great! They add value to students' education by actively providing insights into the learnings and practices of some of the world's best theorists, academicians and business leaders. B-schools certainly do teach you a lot, but then there is more that needs to be learnt.
Initiative and risk-taking: Learning from others' experiences is wise. The successes and failures of individuals and companies have shaped current-day management courses.
Each of those instances was pioneering in its time. There were a small percentage of risk-takers who lived to tell the tale, instantly defining newer paradigms. Each perspective comes with its assumptions and constraints, and it is up to the individual to challenge and break new ground.
Adaptability: To roll with the punches and come on top each time, an individual has to assimilate the operating environment and conditions and, using that as a base, act!
That is easier said than done since the environment itself changes so rapidly - be it politics, the economy, and competition or consumer preference. A motley combination of various, seemingly unrelated, factors interact to create this environment.
Each instance of variation has a counterbalancing impact on some other factor, with a resulting change in the operating environment. The skill to succeed in this ever-changing, always evolving environment resides in the person, not in the B-school he or she went to.
Application: B-school courses use models, metrics and terminology to get potential entrants into corporate roles off to a flying start. They speak of and relate to events in the same way, using the same jargon.
However, the correct application of a model or tool is usually an individual's discretion; it is his or her interpretation of the situation that forces a judgment, accurate or otherwise. The application of learning is the proof of the pudding - a realization of the latent knowledge in an actual business context, which rests squarely on the individual's shoulders.
B-schools, too, work continuously trying to bring in the best inputs possible, in terms of trends, preferences and principles, though the introduction of such knowledge in course curriculum happens only after it has been published or, at least, documented.
This involves significant lag time, and given the breadth and speed of change, this is an uphill and never-ending task.
In sum, a B-school is the basic foundation that equips individuals to get a firm footing in the corporate arena, but there are several other skills that one needs to assimilate to survive and succeed there.
But most important of all - don't forget to live and have fun. It is too easy to get caught up in the rat race; stay out of it. Spend the first few years of your corporate life with your nose down, bury your ego, enjoy every moment of your work and make sure that you do the best you can. Success will follow.
Nalin Garg graduated from Tata Institute of Social Sciences, Mumbai, in 1992
More info @ http://www.rediff.com/money/2007/may/16bschool.htm
Nalin Garg writes:
Business schools are great! They add value to students' education by actively providing insights into the learnings and practices of some of the world's best theorists, academicians and business leaders. B-schools certainly do teach you a lot, but then there is more that needs to be learnt.
Initiative and risk-taking: Learning from others' experiences is wise. The successes and failures of individuals and companies have shaped current-day management courses.
Each of those instances was pioneering in its time. There were a small percentage of risk-takers who lived to tell the tale, instantly defining newer paradigms. Each perspective comes with its assumptions and constraints, and it is up to the individual to challenge and break new ground.
Adaptability: To roll with the punches and come on top each time, an individual has to assimilate the operating environment and conditions and, using that as a base, act!
That is easier said than done since the environment itself changes so rapidly - be it politics, the economy, and competition or consumer preference. A motley combination of various, seemingly unrelated, factors interact to create this environment.
Each instance of variation has a counterbalancing impact on some other factor, with a resulting change in the operating environment. The skill to succeed in this ever-changing, always evolving environment resides in the person, not in the B-school he or she went to.
Application: B-school courses use models, metrics and terminology to get potential entrants into corporate roles off to a flying start. They speak of and relate to events in the same way, using the same jargon.
However, the correct application of a model or tool is usually an individual's discretion; it is his or her interpretation of the situation that forces a judgment, accurate or otherwise. The application of learning is the proof of the pudding - a realization of the latent knowledge in an actual business context, which rests squarely on the individual's shoulders.
B-schools, too, work continuously trying to bring in the best inputs possible, in terms of trends, preferences and principles, though the introduction of such knowledge in course curriculum happens only after it has been published or, at least, documented.
This involves significant lag time, and given the breadth and speed of change, this is an uphill and never-ending task.
In sum, a B-school is the basic foundation that equips individuals to get a firm footing in the corporate arena, but there are several other skills that one needs to assimilate to survive and succeed there.
But most important of all - don't forget to live and have fun. It is too easy to get caught up in the rat race; stay out of it. Spend the first few years of your corporate life with your nose down, bury your ego, enjoy every moment of your work and make sure that you do the best you can. Success will follow.
Nalin Garg graduated from Tata Institute of Social Sciences, Mumbai, in 1992
More info @ http://www.rediff.com/money/2007/may/16bschool.htm
Tsarafara, Madagascar
Tsarafara, near Mount Ibity in the Sahatany Valley of central Madagascar is a well known site that produces crystals of spodumene, morganite and tourmaline of various qualities. The miners use hand methods to find the crystals. Tsarafara is also known as Ankadilava or Ambalaroy in the literature. The colors of spodumene crystals from these mines may range from colorless to pale green, blue and pink. Top quality specimens are sold to collectors from around the world, and the rest are cut and polished at cutting centers in Southeast Asia and South Asia. The colors of tourmaline crystals may range from violet pink, green, dark green, bluish green to yellow, brownish yellow and near colorless. Top quality specimens end up with the collectors, while the low quality tourmalines are sold to African/Asian dealers for beads and carvings. The colors of Morganite crystals may range from pale to yellow orange color. Top quality specimens may show a pleasing orange pink to pink body color. Clean stones may yield beautiful faceted stones. As is the case with most low tech mines in Madagascar flooding during the rainy season can destroy the working mines.
An Interesting Large Mauve Stone
I wonder how many gemologists would go the extra mile to identify an unknown colored stone. They would simply try using the basic tools and if they can't, they just give up. Also, how many even know what a taaffeite is. Sri Lanka, Burma, and Madagascar are treasure troves for the novice and experienced gemologists.
(via The Australian Gemmologist, Vo.23, No.2, April – June 2007)
Some time ago, a large mauve faceted stone was submitted for testing at GSL. This gemstone was among a suite of stones thought to be natural spinels.
When testing the stones, it was noted that the mauve faceted stone had a spot R.I reading of 1.71 and a specific gravity of 3.61, which are within the range of natural spinel. No visible inclusions were noted, and the stone showed no reaction when exposed to ultraviolet light.
However, further investigation showed that the stone showed a doubly refractive behavior on the polariscope and a uniaxial interference figure was noted. When precise refractive index reading were taken they were found to be 1.713 – 1.720 and the optic sign was uniaxial negative. Indeed, these data proved the large faceted mauve gemstone to be a rare taaffeite. This gemstone measured 12.8 x 9.5mm and weighing 5.20 carats.
Of the remainder of the group of spinels (?) submitted for gem testing, another pinkish oval gemstone, weighing 0.90 carat, also was identified as a taaffeite.
(via The Australian Gemmologist, Vo.23, No.2, April – June 2007)
Some time ago, a large mauve faceted stone was submitted for testing at GSL. This gemstone was among a suite of stones thought to be natural spinels.
When testing the stones, it was noted that the mauve faceted stone had a spot R.I reading of 1.71 and a specific gravity of 3.61, which are within the range of natural spinel. No visible inclusions were noted, and the stone showed no reaction when exposed to ultraviolet light.
However, further investigation showed that the stone showed a doubly refractive behavior on the polariscope and a uniaxial interference figure was noted. When precise refractive index reading were taken they were found to be 1.713 – 1.720 and the optic sign was uniaxial negative. Indeed, these data proved the large faceted mauve gemstone to be a rare taaffeite. This gemstone measured 12.8 x 9.5mm and weighing 5.20 carats.
Of the remainder of the group of spinels (?) submitted for gem testing, another pinkish oval gemstone, weighing 0.90 carat, also was identified as a taaffeite.
Trust
2007: Here is a thought-provoking article on disclosure practices for gemologists, lab gemologists, gem dealers, jewelers and consumers. I totally agree with the author.
(via Jewellery News Asia, May 2007) Dr John Emmett writes:
Since early times, gemstones have been objects of desire. Indeed the historical record is littered with examples of wars fought, cities sacked and duels dueled, all to possess these precious objects.
Naturally enough, the scarcity and high value of gems has also led to fraud, as the following selection from Pliny’s History of the World illustrates:
…..Moreover, I have in my library certain books by authors now living, whom I would under no circumstances name….containing, for example, information on how to make a sardonychus (sardonyx) from a sarda (carnelian, in part sard): in other words, how to transform one stone into another. To tell the truth, there is no fraud or deceit in the world that yields greater gain and profit than that of counterfeiting gems.
It is clear from the above ‘improvement’ of lesser stones was not considered a path to heaven, nor did it earn merit for the next lifetime. And yet, what Pliny considered fraud is often referred by some today as: finishing the job that nature started. (Pliny: 23-79 AD)
I do not support such broad-brush rationalization. With definition like this, death simply finishes the job that birth started. I believe what happens in between matters, too.
Value
Everyone is taught that gemstones are valuable for three primary reasons—beauty, rarity and durability. Let’s consider treatments in light of these factors.
The purpose of a treatment is to increase value, usually via improvement in appearance. So what is the relative value of a treated counterpart? If we compare two stones of equal beauty and durability, the only remaining factor is rarity.
Heat
How does heat treatment affect rarity? The answer is dramatically—a radical increase in the number of beautiful stones in the marketplace.
The production of gem quality stones from any mine is only a small fraction of total production. Most specimens are too impure to be cut into gems. Consider Sri Lankan sapphire. Far more geuda (impure corundum) than gem quality sapphire is produced, perhaps 100 times as much. Beginning in the mid-1097s, the widespread adoption of effective treatments for Sri Lankan geuda dramatically increased the availability of fine blue sapphire. This resulted in a stagnation of sapphire prices that has continued for decades. As more and more gems undergo more drastic treatments, we have to ask if this is the future of the gemstone business?
And flux
In the late 1980s, large quantities of heavily fractured purplish rubies were discovered at Mong Hsu, Burma. Enter the oven, exit fine reds, the likes of which had never been previously seen in over two millennia of ruby production. What’s up?
Heating plus flux. The heat banished the blue in the stones, turning purple to red. But what about those cracks? They were also taken care of. Addition of fluxes during the heating process literally dissolved the walls of fractures and redeposited synthetic corundum, healing the problem away. Crack no more. How many customers that purchased these stones were told that they contain microscopic amount of synthetic corundum as fracture filler?
None. No one has been told. Instead the treatment has been obscured by words about glass ‘residues from the heating process’ on laboratory reports. So obtuse is this language that even most dealers are unaware of exactly what has occurred with these stones.
And beryllium
In 2001, again without disclosure, stones treated by a new process entered the market. The color of these stones resulted from diffusing beryllium into them from the outside, just like dyeing cloth. This process allowed one to manufacture yellow, padpardscha, and orange sapphire from low-value starting material. Later, it was shown that beryllium diffusion could also lighten overly dark blue sapphire. Suddenly the search for the Holy Grail was over. This ‘manufacturing’ process had the potential to dramatically rewrite the book on corundum rarity, allowing treaters to almost dye a stone at will.
What is the impact on rarity? Beryllium diffusion can increase the availability of yellow sapphire by a factor of over 1000, and of padparadscha, because of its natural rarity, by even larger factors. The sky is the limit for blue sapphire. What does this say about value?
Disclosure?
Virtually all gem trade associations have treatment disclosure policies. In reading them it is unclear if they are intended to truly inform the buyer or provide legal protections for the seller. It is certainly the rare sales person that can explain what has been done to a stone and put that information in a value-oriented context. In today’s market, value is determined far more by traders than an informed purchasing public.
Consumers are rarely told that this sapphire has been heated above the melting point of steel and thus is a hundred times less rare that a natural sapphire of similar appearance. Nor do many explain to the retail customer that a yellow sapphire was manufactured from nearly colorless low-value corundum via beryllium diffusion.
What might be the value of a heat treated sapphire if a consumer had a full understanding of three realities? Would he or she be willing to pay a hundredth the price of the natural sapphire, a tenth, a third, or more? We simply don’t know. What about stones manufactured by beryllium diffusion?
How about synthetic sapphire? Might retail buyers prefer a large beautiful synthetic sapphire, once they truly understood how close to synthetic so many stones are today? What would happen to values if the arcane knowledge of treatments became public? To date, few customers have been offered an honest description of treatments at the time of purchase. Who knows what might happen if they were?
Rebottling the genie
As we move into the future, gem enhancements will not become any less effective, nor will detection become easier. Increasingly sophisticated treatments have driven the cost of a thorough lab report on a corundum gem to levels that are prohibitive for most gems under few carats. From heated geuda sapphires, through titanium diffusion, glass-cavity filling, flux-fracture healing and beryllium diffusion, the past 30 years have seen one treatment after another foisted upon an unwary world without regard for proper disclosure. We used to believe in magic. We believed everyone could get rich by making silk purses out of sow’s ears. But we failed to see the future.
The future has arrived. Senior industry analyst Russell Shor, in the March 9, 2007 GIA Insider wrote:
“Thailand’s gemstone manufacturing industry is in crisis, according to its leaders, who report that many gem cutters in Chantaburi have closed or suspended operations. The two major trade associations have petitioned the government for funds to promote their gems in world markets and to establish a reasonable, government-sanctioned standard for disclosure of treatments? Exhibitors at the recent Thailand Gems and Jewellery Fair in Bangkok were offering sapphires in a variety of colors for as little as US$5 per carat (less if you wanted to bargain and/or buy in quantity) without a lot of takers. Some exhibitors labeled diffusion treated materials clearly, others did not. Buyers were unsure of what they were getting and, with only sporadic disclosure, sapphire prices for all colors have fallen to the level of greatest doubt.”
We rubbed the magic lamp, the genie granted our wishes. And suddenly we’ve decided we don’t believe in magic after all.
Trust is…
And in the end, the love you take is equal to the love you make (The Beatles, The End).
In recent years, a portion of the gem community has embraced the Fair Trade Movement, which seeks to ensure that mining and cutting of gemstones is carried out under safe, environmentally acceptable conditions, with fair compensation for all involved.
The concept is simple: fair play. It seeks to ensure that no single member of the supply chain can prey upon another. One of the basic tenets of this idea is full disclosure of treatments. Again, the concept is simple: buyers should understand exactly what has been done to a gem before making a purchase decision.
Today, the gulf between disclosure and understanding is not unlike that between birth and death. It is a vast chasm.
What lies between? It is not trivial. Disclosure is not enough. We must explain, we must teach, we must educate. In the end, it’s all about trust. We must trust customers enough to realize that their education and understanding are crucial to everyone’s success. Trust. In the end, it’s no different than love.
(via Jewellery News Asia, May 2007) Dr John Emmett writes:
Since early times, gemstones have been objects of desire. Indeed the historical record is littered with examples of wars fought, cities sacked and duels dueled, all to possess these precious objects.
Naturally enough, the scarcity and high value of gems has also led to fraud, as the following selection from Pliny’s History of the World illustrates:
…..Moreover, I have in my library certain books by authors now living, whom I would under no circumstances name….containing, for example, information on how to make a sardonychus (sardonyx) from a sarda (carnelian, in part sard): in other words, how to transform one stone into another. To tell the truth, there is no fraud or deceit in the world that yields greater gain and profit than that of counterfeiting gems.
It is clear from the above ‘improvement’ of lesser stones was not considered a path to heaven, nor did it earn merit for the next lifetime. And yet, what Pliny considered fraud is often referred by some today as: finishing the job that nature started. (Pliny: 23-79 AD)
I do not support such broad-brush rationalization. With definition like this, death simply finishes the job that birth started. I believe what happens in between matters, too.
Value
Everyone is taught that gemstones are valuable for three primary reasons—beauty, rarity and durability. Let’s consider treatments in light of these factors.
The purpose of a treatment is to increase value, usually via improvement in appearance. So what is the relative value of a treated counterpart? If we compare two stones of equal beauty and durability, the only remaining factor is rarity.
Heat
How does heat treatment affect rarity? The answer is dramatically—a radical increase in the number of beautiful stones in the marketplace.
The production of gem quality stones from any mine is only a small fraction of total production. Most specimens are too impure to be cut into gems. Consider Sri Lankan sapphire. Far more geuda (impure corundum) than gem quality sapphire is produced, perhaps 100 times as much. Beginning in the mid-1097s, the widespread adoption of effective treatments for Sri Lankan geuda dramatically increased the availability of fine blue sapphire. This resulted in a stagnation of sapphire prices that has continued for decades. As more and more gems undergo more drastic treatments, we have to ask if this is the future of the gemstone business?
And flux
In the late 1980s, large quantities of heavily fractured purplish rubies were discovered at Mong Hsu, Burma. Enter the oven, exit fine reds, the likes of which had never been previously seen in over two millennia of ruby production. What’s up?
Heating plus flux. The heat banished the blue in the stones, turning purple to red. But what about those cracks? They were also taken care of. Addition of fluxes during the heating process literally dissolved the walls of fractures and redeposited synthetic corundum, healing the problem away. Crack no more. How many customers that purchased these stones were told that they contain microscopic amount of synthetic corundum as fracture filler?
None. No one has been told. Instead the treatment has been obscured by words about glass ‘residues from the heating process’ on laboratory reports. So obtuse is this language that even most dealers are unaware of exactly what has occurred with these stones.
And beryllium
In 2001, again without disclosure, stones treated by a new process entered the market. The color of these stones resulted from diffusing beryllium into them from the outside, just like dyeing cloth. This process allowed one to manufacture yellow, padpardscha, and orange sapphire from low-value starting material. Later, it was shown that beryllium diffusion could also lighten overly dark blue sapphire. Suddenly the search for the Holy Grail was over. This ‘manufacturing’ process had the potential to dramatically rewrite the book on corundum rarity, allowing treaters to almost dye a stone at will.
What is the impact on rarity? Beryllium diffusion can increase the availability of yellow sapphire by a factor of over 1000, and of padparadscha, because of its natural rarity, by even larger factors. The sky is the limit for blue sapphire. What does this say about value?
Disclosure?
Virtually all gem trade associations have treatment disclosure policies. In reading them it is unclear if they are intended to truly inform the buyer or provide legal protections for the seller. It is certainly the rare sales person that can explain what has been done to a stone and put that information in a value-oriented context. In today’s market, value is determined far more by traders than an informed purchasing public.
Consumers are rarely told that this sapphire has been heated above the melting point of steel and thus is a hundred times less rare that a natural sapphire of similar appearance. Nor do many explain to the retail customer that a yellow sapphire was manufactured from nearly colorless low-value corundum via beryllium diffusion.
What might be the value of a heat treated sapphire if a consumer had a full understanding of three realities? Would he or she be willing to pay a hundredth the price of the natural sapphire, a tenth, a third, or more? We simply don’t know. What about stones manufactured by beryllium diffusion?
How about synthetic sapphire? Might retail buyers prefer a large beautiful synthetic sapphire, once they truly understood how close to synthetic so many stones are today? What would happen to values if the arcane knowledge of treatments became public? To date, few customers have been offered an honest description of treatments at the time of purchase. Who knows what might happen if they were?
Rebottling the genie
As we move into the future, gem enhancements will not become any less effective, nor will detection become easier. Increasingly sophisticated treatments have driven the cost of a thorough lab report on a corundum gem to levels that are prohibitive for most gems under few carats. From heated geuda sapphires, through titanium diffusion, glass-cavity filling, flux-fracture healing and beryllium diffusion, the past 30 years have seen one treatment after another foisted upon an unwary world without regard for proper disclosure. We used to believe in magic. We believed everyone could get rich by making silk purses out of sow’s ears. But we failed to see the future.
The future has arrived. Senior industry analyst Russell Shor, in the March 9, 2007 GIA Insider wrote:
“Thailand’s gemstone manufacturing industry is in crisis, according to its leaders, who report that many gem cutters in Chantaburi have closed or suspended operations. The two major trade associations have petitioned the government for funds to promote their gems in world markets and to establish a reasonable, government-sanctioned standard for disclosure of treatments? Exhibitors at the recent Thailand Gems and Jewellery Fair in Bangkok were offering sapphires in a variety of colors for as little as US$5 per carat (less if you wanted to bargain and/or buy in quantity) without a lot of takers. Some exhibitors labeled diffusion treated materials clearly, others did not. Buyers were unsure of what they were getting and, with only sporadic disclosure, sapphire prices for all colors have fallen to the level of greatest doubt.”
We rubbed the magic lamp, the genie granted our wishes. And suddenly we’ve decided we don’t believe in magic after all.
Trust is…
And in the end, the love you take is equal to the love you make (The Beatles, The End).
In recent years, a portion of the gem community has embraced the Fair Trade Movement, which seeks to ensure that mining and cutting of gemstones is carried out under safe, environmentally acceptable conditions, with fair compensation for all involved.
The concept is simple: fair play. It seeks to ensure that no single member of the supply chain can prey upon another. One of the basic tenets of this idea is full disclosure of treatments. Again, the concept is simple: buyers should understand exactly what has been done to a gem before making a purchase decision.
Today, the gulf between disclosure and understanding is not unlike that between birth and death. It is a vast chasm.
What lies between? It is not trivial. Disclosure is not enough. We must explain, we must teach, we must educate. In the end, it’s all about trust. We must trust customers enough to realize that their education and understanding are crucial to everyone’s success. Trust. In the end, it’s no different than love.
South Australian Diamond Exploration Database
(via Australian Gemmologist, Vol 23, No.1, Jan – Mar, 2007)
SADIEX, the South Australian Diamond Exploration Database, is a free DVD that has been compiled by the Mineral Resources Group, PIRSA (Primary Industries and Resources South Australia). Data readily accessed from this DVD includes exploration results from open file reports from 1990 to present, and additional data from a further 36 open file reports dating between 1969 and 1990. These data have been produced by exploration companies such as Stockdale, CRA Exploration, Diamond Ventures, Tracker Resources and Reedy Lagoon. The DVD also includes Excel spreadsheets containing location data, indicator mineral results and laboratory comments, mineral chemistry of indicator minerals, and trace element and whole rock geochemistry.
Copies of this DVD can be obtained by personal request to the Mineral Resources Group, PIRSA at http://www.pir.sa.gov.au
SADIEX, the South Australian Diamond Exploration Database, is a free DVD that has been compiled by the Mineral Resources Group, PIRSA (Primary Industries and Resources South Australia). Data readily accessed from this DVD includes exploration results from open file reports from 1990 to present, and additional data from a further 36 open file reports dating between 1969 and 1990. These data have been produced by exploration companies such as Stockdale, CRA Exploration, Diamond Ventures, Tracker Resources and Reedy Lagoon. The DVD also includes Excel spreadsheets containing location data, indicator mineral results and laboratory comments, mineral chemistry of indicator minerals, and trace element and whole rock geochemistry.
Copies of this DVD can be obtained by personal request to the Mineral Resources Group, PIRSA at http://www.pir.sa.gov.au
The Versatilist Manager
Nandan Nilekani, CEO and MD of Infosys Technologies writes:
A versatilist has the ability to apply skills more intensively to situations. Hence, they gain new competencies, build new relationships, and assume new roles. One should be equally at ease with technical issues as with business and strategic. You have to synthesize knowledge, experience and the context to create value.
The higher up an individual moves in an organisation, the more he needs to look at the big picture, understand more than one role and develop skills relevant to it— and the more he can be likened to an octopus with each tentacle dealing with a different aspect of the business. The need is to apply a plethora of roles and skills to create a new way of solving problems or taking decisions.
Useful link:
www.infosys.com
A versatilist has the ability to apply skills more intensively to situations. Hence, they gain new competencies, build new relationships, and assume new roles. One should be equally at ease with technical issues as with business and strategic. You have to synthesize knowledge, experience and the context to create value.
The higher up an individual moves in an organisation, the more he needs to look at the big picture, understand more than one role and develop skills relevant to it— and the more he can be likened to an octopus with each tentacle dealing with a different aspect of the business. The need is to apply a plethora of roles and skills to create a new way of solving problems or taking decisions.
Useful link:
www.infosys.com
Friday, May 18, 2007
Large Diamond From the USA
(via Australian Gemmologist, Vol.23, No.1, Jan – Mar, 2007)
The Crater of Diamonds State Park in Murfreesboro, Arkansas, has yielded its second large diamond in as many months. A tourist named Bob Wehle, from Ripon, Wisconsin, found a 5.47 carat canary yellow diamond in the park on October 14, 2006.
In September, Donald and Brenda Roden, of Point, Texas, found a 6.35 carat diamond at the Park, which is the only park in the world where tourists can look for and keep any diamonds they find.
Park officials said they are not in the business of estimating the value of diamonds visitors find, but a 4.21 carat flawless canary yellow diamond found in March was estimated to be worth US$15000—US$60000 by a New York diamond dealer. The park is the site of the largest diamond ever found in the United States—a 40.23 carat stone (lower LHS) dug in 1924 and dubbed the Uncle Sam diamond after it was faceted into a 12.42 carat emerald cut diamond (lower RHS).
Notable diamonds recovered from Arkansas Crater of Diamonds include:
1. Uncle Sam:
Date found: 1924
Uncut weight: 40.23 carats
Cut weight: 12.42 carats
Color: white
2. Amarillo Starlight
Date found: 1975
Uncut weight: 16.37 carats
Cut weight: 7.54 carats
Color: white
3. Star of Arkansas
Date found: 1956
Uncut weight: 15.33 carats
Cut weight: 8.27 carats
Color: white
4. Star of Shreveport
Date found: 1981
Uncut weight: 8.82 carats
Cut weight: uncut
Color: white
5. Lamle diamond
Date found: 1978
Uncut weight: 8.61 carats
Cut weight: -
Color: brown
6. Connell diamond
Date found: 1986
Uncut weight: 7.95 carats
Cut weight: -
Color: white
7. Stevens/Dickenson diamond
Date found: 1998
Uncut weight: 7.28 carats
Cut weight: uncut
Color: yellow
8. Cooper diamond
Date found: 1997
Uncut weight: 6.72 carats
Cut weight: uncut
Color: brown
9. Gary Moore diamond
Date found: 1960
Uncut weight: 6.43 carats
Cut weight: uncut
Color: canary
10. Lee diamond
Date found: 1988
Uncut weight: 6.30 carats
Cut weight: -
Color: white
11. Newman diamond
Date found: 1981
Uncut weight: 6.25 carats
Cut weight: -
Color: white
12. Fedzora diamond
Date found: 1991
Uncut weight: 6.23 carats
Cut weight: -
Color: white
13. Stockton diamond
Date found: 1981
Uncut weight: 6.20 carats
Cut weight: -
Color: white
14. Schall diamond
Date found: 1981
Uncut weight: 6.07 carats
Cut weight: -
Color: white
15. Cooper diamond
Date found: 1997
Uncut weight: 6.00 carats
Cut weight: -
Color: brown
16. Kahn Canary
Date found: 1977
Uncut weight: 4.25 carats
Cut weight: uncut
Color: canary
17. Strawn – Wagner diamond
Date found: 1990
Uncut weight: 3.03 carats
Cut weight: 1.09 carats
Color: white
This list of notable diamond from Crater of Diamonds includes all diamonds weighing six carats or more, and the much publicized ‘Strawn – Wagner Diamond’.
More info @ www.arkansasstateparks.com
The Crater of Diamonds State Park in Murfreesboro, Arkansas, has yielded its second large diamond in as many months. A tourist named Bob Wehle, from Ripon, Wisconsin, found a 5.47 carat canary yellow diamond in the park on October 14, 2006.
In September, Donald and Brenda Roden, of Point, Texas, found a 6.35 carat diamond at the Park, which is the only park in the world where tourists can look for and keep any diamonds they find.
Park officials said they are not in the business of estimating the value of diamonds visitors find, but a 4.21 carat flawless canary yellow diamond found in March was estimated to be worth US$15000—US$60000 by a New York diamond dealer. The park is the site of the largest diamond ever found in the United States—a 40.23 carat stone (lower LHS) dug in 1924 and dubbed the Uncle Sam diamond after it was faceted into a 12.42 carat emerald cut diamond (lower RHS).
Notable diamonds recovered from Arkansas Crater of Diamonds include:
1. Uncle Sam:
Date found: 1924
Uncut weight: 40.23 carats
Cut weight: 12.42 carats
Color: white
2. Amarillo Starlight
Date found: 1975
Uncut weight: 16.37 carats
Cut weight: 7.54 carats
Color: white
3. Star of Arkansas
Date found: 1956
Uncut weight: 15.33 carats
Cut weight: 8.27 carats
Color: white
4. Star of Shreveport
Date found: 1981
Uncut weight: 8.82 carats
Cut weight: uncut
Color: white
5. Lamle diamond
Date found: 1978
Uncut weight: 8.61 carats
Cut weight: -
Color: brown
6. Connell diamond
Date found: 1986
Uncut weight: 7.95 carats
Cut weight: -
Color: white
7. Stevens/Dickenson diamond
Date found: 1998
Uncut weight: 7.28 carats
Cut weight: uncut
Color: yellow
8. Cooper diamond
Date found: 1997
Uncut weight: 6.72 carats
Cut weight: uncut
Color: brown
9. Gary Moore diamond
Date found: 1960
Uncut weight: 6.43 carats
Cut weight: uncut
Color: canary
10. Lee diamond
Date found: 1988
Uncut weight: 6.30 carats
Cut weight: -
Color: white
11. Newman diamond
Date found: 1981
Uncut weight: 6.25 carats
Cut weight: -
Color: white
12. Fedzora diamond
Date found: 1991
Uncut weight: 6.23 carats
Cut weight: -
Color: white
13. Stockton diamond
Date found: 1981
Uncut weight: 6.20 carats
Cut weight: -
Color: white
14. Schall diamond
Date found: 1981
Uncut weight: 6.07 carats
Cut weight: -
Color: white
15. Cooper diamond
Date found: 1997
Uncut weight: 6.00 carats
Cut weight: -
Color: brown
16. Kahn Canary
Date found: 1977
Uncut weight: 4.25 carats
Cut weight: uncut
Color: canary
17. Strawn – Wagner diamond
Date found: 1990
Uncut weight: 3.03 carats
Cut weight: 1.09 carats
Color: white
This list of notable diamond from Crater of Diamonds includes all diamonds weighing six carats or more, and the much publicized ‘Strawn – Wagner Diamond’.
More info @ www.arkansasstateparks.com
Standards For Testing Jadeite
(via Australian Gemmologist, Vol. 23, No.2, April-June 2007)
In late 2006, The Gemmological Association of Hong Kong released HKSM/JJT-2006 titled ‘Standard methods for testing Fei Cui (jadeite jade) for Hong Kong.
This standard has been prepared in consultation with members of the Hong Kong gemstone and jewelry industries via the Task Force for Gemstone Testing—a body established under the Accreditation Advisory Board of the Hong Kong Accreditation Service. This 2006 version replaces a previous 2004 version.
The stated purpose of this standard is:
1. Definition of the nomenclature for Fei Cui.
2. Provide standardized practice and methodology for testing Fei Cui, and,
3. Provide set technical specifications for the format and comments used when issuing certificates of identity for Fei Cui.
Contents of this standard begins with a precise definition of Fei Cui, its major physical properties, and a tabulation of the various types of Fei Cui (Types A, B, C, and B+C) that are available commercially. Systematic standard testing methods are then described for shape and cut, dimensions, weight, transparency, color, polariscope examination, refractive index, specific gravity, fluorescence, Chelsea Filter reaction, VIS absorption spectroscopy, microscope examination, and FTIR spectroscopy. Chinese language versions of the definitions of Fei Cui, its properties and its various types are presented in three appendices at the end of the standard.
This precise, standardized approach to testing Fei Cui deserves to be copied for testing other major gemstones.
In late 2006, The Gemmological Association of Hong Kong released HKSM/JJT-2006 titled ‘Standard methods for testing Fei Cui (jadeite jade) for Hong Kong.
This standard has been prepared in consultation with members of the Hong Kong gemstone and jewelry industries via the Task Force for Gemstone Testing—a body established under the Accreditation Advisory Board of the Hong Kong Accreditation Service. This 2006 version replaces a previous 2004 version.
The stated purpose of this standard is:
1. Definition of the nomenclature for Fei Cui.
2. Provide standardized practice and methodology for testing Fei Cui, and,
3. Provide set technical specifications for the format and comments used when issuing certificates of identity for Fei Cui.
Contents of this standard begins with a precise definition of Fei Cui, its major physical properties, and a tabulation of the various types of Fei Cui (Types A, B, C, and B+C) that are available commercially. Systematic standard testing methods are then described for shape and cut, dimensions, weight, transparency, color, polariscope examination, refractive index, specific gravity, fluorescence, Chelsea Filter reaction, VIS absorption spectroscopy, microscope examination, and FTIR spectroscopy. Chinese language versions of the definitions of Fei Cui, its properties and its various types are presented in three appendices at the end of the standard.
This precise, standardized approach to testing Fei Cui deserves to be copied for testing other major gemstones.
Indo-US Jewelry Business Development Conference
The Gem & Jewellery Export Promotion Council of India will be hosting the first Indo-US Jewelry Business Development Conference for jewelry retailers on October 1-5 at Mumbai's Marriott Renaissance.
Top U.S and Canadian senior business development executives and directors of merchandise are invited to attend the all-expense paid, jewelry business development event. The event is being organized by GJEPC, and R&B Partners, LLP, a Stamford, Conn.-based branding, marketing, and special event consulting firm.
Top U.S and Canadian senior business development executives and directors of merchandise are invited to attend the all-expense paid, jewelry business development event. The event is being organized by GJEPC, and R&B Partners, LLP, a Stamford, Conn.-based branding, marketing, and special event consulting firm.
A Question Of Origin: A Different View
(via Gemological Digest, Vol.3, No.1, 1990) Grahame Brown writes:
Your well documented arguments against using origin reports to support price premiums for selected colored stones, should stimulate gemologists to think this very real problem through, rather than dismissing your arguments as being commercially unrealistic, or worse still, acquiescing to the rather dubiously based status quo.
Personally, I fully support the general thrust of your arguments, and wish to raise several additional points for consideration.
1. Researchers, species collectors and investors, excepted, why do human beings purchase colored stones? Surely the major factor influencing the desirability and subsequent purchase of a colored stone must be those visual characteristics contributing to the particular gem’s beauty and rarity. It is a fact that geography has little proven influence over the appearance of a colored stone.
2. Why should the presence of any visually detectable inclusion (s) in a colored stone not logically degrade, rather than sometimes upgrade, the value of the stone? Clarity should be a significant determinant of value; the country of origin of the gemstone’s inclusion should not practically influence its global value.
3. If origin reports are of such significance to the value of colored stones, why are these not routinely prepared for all colored stones?
4. If the gemologist wishes, or is forced by perceived necessity, to issue an origin report for a particular colored stone, then what data does he or she have to support their assignment of origin to that colored stone? The factual answer to this question is……precious little. Certainly, several most useful photoatlases of gemstone inclusions have been published, but none of these present an exhaustive review of characteristic inclusions found in colored stones from all past or present mines. This comparative information is essential if the origin of a colored stone is to be determined with any degree of accuracy. Yes, systematic collections of colored stones do exist, e.g. the GIA’s reference collection, but this collection is not readily accessible to an antipodean gemologist, who may be attempting to determine the origin of a troublesome colored stone. Excellent though the GIA reference collection is….is still incomplete. Perhaps the most striking inadequacy of gemology’s knowledge of characteristic gemstone inclusions is the fact that less than 50 per cent (author’s estimate) of the world’s colored stone deposits have been described, in any way, in the gemological literature. Simply put, insufficient data exists to allow error-free origin reports to be issued by the majority of gemologists.
Origin reports for colored stones may be economic necessity for some gemologists, but to me (for the reasons expressed above) they mostly represent quasi-scientific gemological humbug.
Your well documented arguments against using origin reports to support price premiums for selected colored stones, should stimulate gemologists to think this very real problem through, rather than dismissing your arguments as being commercially unrealistic, or worse still, acquiescing to the rather dubiously based status quo.
Personally, I fully support the general thrust of your arguments, and wish to raise several additional points for consideration.
1. Researchers, species collectors and investors, excepted, why do human beings purchase colored stones? Surely the major factor influencing the desirability and subsequent purchase of a colored stone must be those visual characteristics contributing to the particular gem’s beauty and rarity. It is a fact that geography has little proven influence over the appearance of a colored stone.
2. Why should the presence of any visually detectable inclusion (s) in a colored stone not logically degrade, rather than sometimes upgrade, the value of the stone? Clarity should be a significant determinant of value; the country of origin of the gemstone’s inclusion should not practically influence its global value.
3. If origin reports are of such significance to the value of colored stones, why are these not routinely prepared for all colored stones?
4. If the gemologist wishes, or is forced by perceived necessity, to issue an origin report for a particular colored stone, then what data does he or she have to support their assignment of origin to that colored stone? The factual answer to this question is……precious little. Certainly, several most useful photoatlases of gemstone inclusions have been published, but none of these present an exhaustive review of characteristic inclusions found in colored stones from all past or present mines. This comparative information is essential if the origin of a colored stone is to be determined with any degree of accuracy. Yes, systematic collections of colored stones do exist, e.g. the GIA’s reference collection, but this collection is not readily accessible to an antipodean gemologist, who may be attempting to determine the origin of a troublesome colored stone. Excellent though the GIA reference collection is….is still incomplete. Perhaps the most striking inadequacy of gemology’s knowledge of characteristic gemstone inclusions is the fact that less than 50 per cent (author’s estimate) of the world’s colored stone deposits have been described, in any way, in the gemological literature. Simply put, insufficient data exists to allow error-free origin reports to be issued by the majority of gemologists.
Origin reports for colored stones may be economic necessity for some gemologists, but to me (for the reasons expressed above) they mostly represent quasi-scientific gemological humbug.
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