Tuesday, June 12, 2007
What Percentage Of Gold Is Used In Jewelry, Industry And Investment?
(via Commodity Online) Around 70% of gold demand is jewelry, 11% is industrial (dental, electronics) and 13% is investment (institutional and individual, bars & coins). Gold jewelry has strong investment attributes in all countries, and in markets such as India and Middle East is sold by weight at the prevailing daily rate with a supplementary 'making charge' which varies according to the complexity of the piece.
Golden Amphibolite (GoldStone) From Near Port Hedland, W.A
I have seen the rough and cut specimens. The cut specimens are attractive. I also know that a famous temple in Thailand is buying the stones for making amulets and carvings. This goldstone is natural, but there is also man-made glass called goldstone which is a simulant/substitute for sunstone.
Dr Robert R Coenraads (Nikiticorp Australia Pty Ltd) writes:
Summary
Samples of a gem material called ‘Goldstone’ provided to Dr Coenraads by Nikiticorp for gemological testing have proved to be amphibolite, a rare metamorphic rock consisting almost entirely of the mineral amphibole. The amphibole mineral has now been largely altered to hematite, goethite and quartz and it displays a magnificent golden iridescence. This rare material is known only from two other localities in the world, Greenland and Wyoming, USA. Trial lapidary work carried out on this material shows it to be hard (approximately 6 of Moh’s scale) and capable of taking a high polish. The golden iridescence is best displayed at certain orientations so some care must be taken when cutting the rough material.
Introduction
Several kilograms of rough material being called ‘goldstone’ were provided to Dr Robert Coenraads by Nikiticorp Pty Ltd for examination. The material was sliced using a slabbing saw at the Wingala Lapidary Association in Sydney. The rough was sawn in three perpendicular directions, polished and photographed. This was to look for any observable difference in appearance of the material at different orientations. Cabochons were also prepared from some of the slices. A sample was provided to Mr Rad Flossman of the University of New South Wales in Sydney to prepare a microscope thin section for petrological study. Another sample was given to Dr Peter Williams for X-ray diffraction analysis at University of Western Sydney.
Description of the samples
The rough material is not particularly attractive being dull yellow or rusty red brown and powdery in appearance. The rough pieces provided were plate-like, that is larger in two dimensions than the third. When polished, however, the samples show a brilliant and unexpected golden iridescence. Noting the orientation of the cuts with respect to the shape of the material revealed that most beautiful iridescence was obtained when the sample was cut in one of the directions perpendicular to the large face of the rough material. In this direction almost all the grains will appear golden in polished surfaces. In the second direction at right angles and perpendicular to the large face, and in the third direction parallel to the large face of the rough most of the grains appear dark brown, although some show the golden iridescence.
X-ray diffraction analysis
The XRD work shows that the samples from Port Hedland are quite similar to those from Wyoming in that the original amphiboles have been largely altered to the iron oxide minerals, hematite and goethite, and quartz as a result of some form of secondary alteration process. This alteration is probably responsible for the iridescent color being so rich and golden. The XRF pattern also showed that traces of the original amphibole remain within the rock and identified them as either grunerite, manganogrunerite (dannemorite) or cummingtonite.
The thin section also reveals that the original amphibole crystals are oriented, probably as a result of directed pressure causing them to grow in that alignment during their metamorphic formation. It also appears that in some of the samples, the layers that were almost entirely made up of amphibole are interlayered with thin layers of almost pure quartz.
Gemological testing
The four ‘goldstone’ cabochons were tested at the Gemological Association of Australia laboratory. The material was found to be inert under LW and SW ultraviolet light, to have an indeterminate spot refractive index around 1.5 to 1.6, and a specific gravity around 2.60 to 2.80. Being a rock rather than a single mineral the tests for specific gravity and refractive index were considered not to be of use in identification of this gemstone. The binocular microscope and hand lens provide the most positive form of identification; that is this gem stunning visual appearance of the interlocking grains and distinctive golden iridescent sheen.
Previous studies
Amphibole is known from only two other localities in the world:
1. A gem quality iridescent orthoamphibole found near Nuuk, the capital of Greenland.
2. A gem quality iridescent orthoamphibole found near Douglas, in Converse County, Wyoming, USA.
The orthoamphiboles from Greenland were shown by Appel and Jensen (1987) to be solid solutions between the end members anthophyllite and gerdite. The iridescence colors are green, blue, through yellow to gold, red and violet (rare), and are caused by diffraction of light from lamellae of amphibole less than 0.2 um thick. The material has a hardness of 6 and an SG between 3.18 and 3.37. Refractive index is 1.64 to 1.66, with a birefringence of 0.02.
The material from Wyoming is different in that it now consists almost entirely of goethite and/or opaline silica which appears to be derived from weathering of the original ferroanthophyllite. The iridescence of the Wyoming material is mainly golden or dark brown with some red or silver gray.
Comparisons between the polished Western Australian ‘goldstone’ and photographs of polished samples from Greenland and USA suggest that the Western Australian material has a larger percentage of its surface displaying the golden iridescence and therefore it is a more attractive material.
Dr Robert R Coenraads (Nikiticorp Australia Pty Ltd) writes:
Summary
Samples of a gem material called ‘Goldstone’ provided to Dr Coenraads by Nikiticorp for gemological testing have proved to be amphibolite, a rare metamorphic rock consisting almost entirely of the mineral amphibole. The amphibole mineral has now been largely altered to hematite, goethite and quartz and it displays a magnificent golden iridescence. This rare material is known only from two other localities in the world, Greenland and Wyoming, USA. Trial lapidary work carried out on this material shows it to be hard (approximately 6 of Moh’s scale) and capable of taking a high polish. The golden iridescence is best displayed at certain orientations so some care must be taken when cutting the rough material.
Introduction
Several kilograms of rough material being called ‘goldstone’ were provided to Dr Robert Coenraads by Nikiticorp Pty Ltd for examination. The material was sliced using a slabbing saw at the Wingala Lapidary Association in Sydney. The rough was sawn in three perpendicular directions, polished and photographed. This was to look for any observable difference in appearance of the material at different orientations. Cabochons were also prepared from some of the slices. A sample was provided to Mr Rad Flossman of the University of New South Wales in Sydney to prepare a microscope thin section for petrological study. Another sample was given to Dr Peter Williams for X-ray diffraction analysis at University of Western Sydney.
Description of the samples
The rough material is not particularly attractive being dull yellow or rusty red brown and powdery in appearance. The rough pieces provided were plate-like, that is larger in two dimensions than the third. When polished, however, the samples show a brilliant and unexpected golden iridescence. Noting the orientation of the cuts with respect to the shape of the material revealed that most beautiful iridescence was obtained when the sample was cut in one of the directions perpendicular to the large face of the rough material. In this direction almost all the grains will appear golden in polished surfaces. In the second direction at right angles and perpendicular to the large face, and in the third direction parallel to the large face of the rough most of the grains appear dark brown, although some show the golden iridescence.
X-ray diffraction analysis
The XRD work shows that the samples from Port Hedland are quite similar to those from Wyoming in that the original amphiboles have been largely altered to the iron oxide minerals, hematite and goethite, and quartz as a result of some form of secondary alteration process. This alteration is probably responsible for the iridescent color being so rich and golden. The XRF pattern also showed that traces of the original amphibole remain within the rock and identified them as either grunerite, manganogrunerite (dannemorite) or cummingtonite.
The thin section also reveals that the original amphibole crystals are oriented, probably as a result of directed pressure causing them to grow in that alignment during their metamorphic formation. It also appears that in some of the samples, the layers that were almost entirely made up of amphibole are interlayered with thin layers of almost pure quartz.
Gemological testing
The four ‘goldstone’ cabochons were tested at the Gemological Association of Australia laboratory. The material was found to be inert under LW and SW ultraviolet light, to have an indeterminate spot refractive index around 1.5 to 1.6, and a specific gravity around 2.60 to 2.80. Being a rock rather than a single mineral the tests for specific gravity and refractive index were considered not to be of use in identification of this gemstone. The binocular microscope and hand lens provide the most positive form of identification; that is this gem stunning visual appearance of the interlocking grains and distinctive golden iridescent sheen.
Previous studies
Amphibole is known from only two other localities in the world:
1. A gem quality iridescent orthoamphibole found near Nuuk, the capital of Greenland.
2. A gem quality iridescent orthoamphibole found near Douglas, in Converse County, Wyoming, USA.
The orthoamphiboles from Greenland were shown by Appel and Jensen (1987) to be solid solutions between the end members anthophyllite and gerdite. The iridescence colors are green, blue, through yellow to gold, red and violet (rare), and are caused by diffraction of light from lamellae of amphibole less than 0.2 um thick. The material has a hardness of 6 and an SG between 3.18 and 3.37. Refractive index is 1.64 to 1.66, with a birefringence of 0.02.
The material from Wyoming is different in that it now consists almost entirely of goethite and/or opaline silica which appears to be derived from weathering of the original ferroanthophyllite. The iridescence of the Wyoming material is mainly golden or dark brown with some red or silver gray.
Comparisons between the polished Western Australian ‘goldstone’ and photographs of polished samples from Greenland and USA suggest that the Western Australian material has a larger percentage of its surface displaying the golden iridescence and therefore it is a more attractive material.
Coolomon Mining
A gem miner's life is tough with endless changes in all things. Here is the real story of a miner and his passion for stones.
(via Gemmology Queensland, Vol.8, Issue 5, May 2007) Jim Elliot writes:
It seems a very long time since my last report as there has been so much going on in our lives. We live in a world of seemingly endless change in all things—except, of course, the damned dry weather over most of the continent.
The Central Queensland Gemfields had sufficient rain over the summer months to bring up a body of grass, which has now dried off and is likely to pose a serious fire threats in the winter months. However, there was only very patchy heavy rain and, as a result, our mine dams are either very low or empty—thus preventing a start up of mining operations once again.
Our cattle property at Calliope is in a belt of very badly droughted country and like many others, we are forced to continue hand feeding our stock and are finding it continually harder to source any supplies of hay for this purpose.
On the other extreme, we have still not been able to commence mining this year at our Lava Plains operation in North Queensland, because it will not stop raining. Once you get north of a line roughly west from the Mackay—Bowen area, everything is green, the creeks have water in them and the cattle are fat. It is only eighteen months since we put a very expensive deep bore down at Lava Plains because it was so dry there, and it worked well—it has rained ever since.
The Gemfields
The Gemfields is just awakening from its quiet time during the hotter months, and there appears to be a steady stream of tourists and hand miners returning to the area, which augurs well for the coming winter season.
By all the reports received, the local jewelers and tourist outlets enjoyed a good season last year despite the dire predictions that people would not travel because of the high fuel prices, and I expect that this year might even improve on the last one. The Sunday markets are well patronized and there are a number of new stalls among the familiar faces.
The very dry conditions will make life difficult for a lot of miners, especially as the Emerald Shire Council has not relented on its decision not to provide the reticulated water to mining claims, but miners are a determined lot and will overcome most difficulties thrown up by bureaucracy.
Our mining operations
Our plans to cut back our activities in order to make life easier do not seem to be working. The demand for quality natural Australian sapphires has grown to the point that, while we are prevented from actual mining by dry conditions in Central Queensland and by wet weather at Lava Plains, we are busier than ever.
We had already moved our Lava Plains mine to the new area on the east side of the Kennedy Highway and were producing very high grade blue sapphire. Just when we were considering selling the Lava Plains operation, our supervisor John Fischer moved the mining pit area and found what we believe to be some of the nicest sapphire that has ever been found anywhere in Australia. It is still mainly of smaller size, but quite the most beautiful blue.
We are also in the process of relocating our Gemfields operation from the ‘Rush’ and ‘Ricebowl’ areas at the Sapphire end, where we have mined for several years, back to the 50 acres of lease area we hold in the ‘The Scrub’ at the Rubyvale end. The Scrub area is famous for its larger and most beautiful blue and particolor stones and was one of the first areas to be worked by the machine miners. We have hung on to this area, waiting for the market conditions to support the increased costs resulting from the more difficult treatment process, and the lower amount of sapphire recovered from the very clay-bound wash.
While the ‘Rush’ and ‘Ricebowl’ areas produce a greater amount of sapphire, it is mostly of a quality more suited to the ‘commercial’ trade end and, as such, was largely sold to visiting Asian buyers. Since the visits of the Asian buyers have all but stopped, our business is now based on the supply of high quality cut sapphires to Australian jewelers, and we hope that the move back to the Scrub area will enable us to produce larger, top grade material, albeit in smaller quantities.
We will offer our 200 acres of leases, plant and plantsite at the Sapphire end for sale. While they no longer form part of our planned operation, they remain a valuable commodity for anyone who has a need for proven larger, efficient treatment system to produce the commercial sapphire found in this area.
Gem shows and jewelry fairs
We have already attended the North Brisbane Lapidary Club show, the Brisbane JAA Jewelry Fair and the Australian Gemboree, which was held at Gatton this year. All these shows were excellent, both in their organizational aspects and in the commercial returns achieved.
It appears to me that, for the last few years, many discerning buyers have been aware that the sale of faked gemstone material, whether it be synthetic, dyed, chemically treated, irradiated or whatever, has largely been undisclosed, and they have lacked the confidence to buy.
Many trade people were also content to buy the cheap, mostly Asian, products in the knowledge that they could resell them at a significant profit to less discerning buyers, even though they had no idea of the true nature of the product they sold.
As a result of TV programs about problems in the jewelry industry, and with the assistance of the brochures put out by the ACCC which both reminded sellers of their responsibilities under government legislation and buyers of their rights and protection, buyers now seem to be even more aware of the adulterated gem material that is on the market, but are prepared to take the trouble to ask questions so that they can satisfy themselves that they are getting what they want—and very importantly, once satisfied, they are prepared to buy.
It was very pleasing to note that, at the shows we have attended, the true nature and treatment status of gemstones was generally clearly displayed for the customers to see, and I hope that all future shows insist on this, and monitor compliance.
There is nothing wrong with a treated or synthetic gemstone, as along as it is sold as such, and is priced accordingly. I was personally very disappointed that the show that the ‘Jewellery World’ magazine had planned for Sydney later this year is not going ahead, as many of the principles espoused by the organizers mirrored my own convictions on what is in the best interests of the genuine Australian manufacturing jewelers, in order to provide for the longevity of our Australian Gemstone and Jewellery manufacturing industries.
Website sales list
We have experienced a significant increase in the demand for significant sapphires, particularly greens, parti-colors and the rarer yellows. Many of these fancy sapphires are found in the hand mining areas and many of the hand miners have some absolutely fabulous stones, but no way to market them.
We have therefore set a system on our second website http://www.australiansapphire.com/ to allow the small scale miners and others to present their stones for sale. We intend that this service may be used for any genuine Australian gemstone, and not just sapphires. We do not collect any cut or commission from the sale of other people’s stones on this website. Any dealing is solely between the buyer and the seller.
We do require that sellers sign a declaration that all gems placed on this sale list be guaranteed to be genuine, natural gemstones of Australian origin and, as always, we recommend that buyers ask for a clearly written certificate of authenticity or similar statement signed by the seller.
Faceting courses
The faceting courses organized by the Queensland Sapphire Producers Association in conjunction with the Gemfields Lions Club and run by John Broadfoot have continued to be a great success, with every course fully subscribed, which gives hope for the continuation of the cutting of at least a portion of our production within Australia, thus retaining jobs in our own area.
There also now seems to be a growing shortage of trained jewelers, by that I mean real manufacturing jewelers, not those who just resell goods that were manufactured overseas and imported into Australia, and I hope that the people in charge of our training systems will address this problem before it too has an impact on our ability to produce genuine local products, at an affordable price, for those customers who are proud to buy Australian.
Chrysoprase
As I detailed in an earlier report, we were given the opportunity to mine and purchase a quantity of chrysoprase from the Marlborough deposit, north of Rockhampton. We have completed that mining, but we have some 50 tons of rough chrysoprase stockpiled on our Calliope cattle property.
The rough chrysoprase varies from smaller pieces to boulders of several kilos, up to a ton (or several tons), with the largest being over 16 tons. The color varies from the darker green to a bright, translucent peppermint green, to the paler colors of the parent chalcedony. We do not intend to break down the larger boulders as we believe that, in time, they will become quite valuable as major carving pieces.
We have now had time to produce a fair quantity of finished material from this stockpile, including good quality cabochons, lovely beads and some amazing carved pieces. The beads are most beautiful, and start at less than 40 cents per carat for the paler colors, but can go up to $5.00 per carat for the jade green colors.
In keeping with our philosophy on gemstones, all this material is sold as completely natural, with no treatment or dyeing whatsoever. We have also used our 24 inch slabbing saw to produce slabs which can be used for bases for clocks, desk equipment or just for the beauty of the material itself.
Our partner in the chrysoprase venture is Rick Hodel who lives in the northern suburbs of Brisbane, and is willing to visit potential clients in the south east corner of Queensland. You can contact him on: 07 3888 3280 or on mobile 0427 265 045
Black spinel
For many years, the sapphire miners have recovered a gemstone called black spinel (a.k.a pleonaste) which has always been discarded as being of too low a value to worry about. When either cabbed or faceted, polished beads or carved, this material actually produces the most beautiful gems. It is harder and more lustrous than onyx, and takes a very fine polish.
While there is currently a limited use of this material as a gemstone in its own right, it produces the most beautiful black beads, which we supply to jewelers in temporary strings in a variety of shapes and sizes, and at prices around 40 cents per carat.
Zeolite
Ad the time of last report, I mentioned that we were fattening some steers in our feedlot on our cattle property with a feed ration that included 5% zeolite powder. I can now report that these steers fattened beautifully, and we were absolutely amazed at the totally spotless condition of their livers and kidneys when they were slaughtered. For those of you who do not recognize the significance of this, it is most unusual for animals subjected to feedlot conditions not to have some form of lesions or marking of the livers and kidneys, and the condition of these organs is considered an important measure of the animal’s health.
We continue to be able to supply, at no cost, this powdered zeolite material to the many persons requesting it for personal use an aid in controlling the effects of many ailments which we understand, includes cancerous conditions and blood related disorders. We do this on firm understanding that persons requesting it do so with no assurances or guarantees, as in this country there still has not been any testing or clinical trials of this naturally occurring material, only a great deal of anecdotal evidence from people who are using it.
Hardly a day goes by without a call from someone to thank for sending them some of this powder and to tell us of benefits they have derived from its use. It is such a pity that this information is not being obtained by trained persons under controlled conditions, and subject to the strict analysis needed for its approval for medicinal use.
We understand the mine which produces this material is being sold at present, and we hope that we will be able to continue obtaining powder from the new owners. We would have loved to purchase the mine ourselves, but we are trying hard to slow down, not to take on new responsibilities. We trust that you will all join us in praying for rain for all those individuals and industries so badly affected by the widespread drought, and all those of you in the flooded northern regions who are sick of rain can join and pray too for a more even distribution of this most precious commodity.
I must admit that I do not entirely agree with the current politically popular theory that this drought is all due to man-induced global warming. Our rough sapphire at Lava Plains is often fractured because it was expelled into a frozen landscape during geologically recent ice age, so there has been a bit of warming going on for several thousand years, and there have been many droughts as serious as the one we are now experiencing.
I think that, to a large extent, the politicians of all colors, State and Federal, are desperately trying to cover their backsides for their failure to take any positive action on either construction of new dams or more importantly on better use by industry of recycled water to minimize the amount of new water required by the reticulation systems in our cities.
It would appear to be commonsense that the first priority would be to ensure the efficient utilization of every drop of water pumped out of the storages, and that it should not be necessary to even consider the use of treated water for human consumption until there is 100% use of recycled water by industry and on parks and gardens, sporting ovals etc.
People in towns and cities in our area have been discouraged for years from having domestic water tanks, despite the fact that many of us in more remote areas have learned to live solely on the water we collect in them. Now the same councils and governments are falling over themselves trying to promote such obvious measures.
I’m sorry for the lecture, but we seem to be governed by blind idiots, but then again, it may just be that I am trying not to sound too cynical about their ultimate agendas.
(via Gemmology Queensland, Vol.8, Issue 5, May 2007) Jim Elliot writes:
It seems a very long time since my last report as there has been so much going on in our lives. We live in a world of seemingly endless change in all things—except, of course, the damned dry weather over most of the continent.
The Central Queensland Gemfields had sufficient rain over the summer months to bring up a body of grass, which has now dried off and is likely to pose a serious fire threats in the winter months. However, there was only very patchy heavy rain and, as a result, our mine dams are either very low or empty—thus preventing a start up of mining operations once again.
Our cattle property at Calliope is in a belt of very badly droughted country and like many others, we are forced to continue hand feeding our stock and are finding it continually harder to source any supplies of hay for this purpose.
On the other extreme, we have still not been able to commence mining this year at our Lava Plains operation in North Queensland, because it will not stop raining. Once you get north of a line roughly west from the Mackay—Bowen area, everything is green, the creeks have water in them and the cattle are fat. It is only eighteen months since we put a very expensive deep bore down at Lava Plains because it was so dry there, and it worked well—it has rained ever since.
The Gemfields
The Gemfields is just awakening from its quiet time during the hotter months, and there appears to be a steady stream of tourists and hand miners returning to the area, which augurs well for the coming winter season.
By all the reports received, the local jewelers and tourist outlets enjoyed a good season last year despite the dire predictions that people would not travel because of the high fuel prices, and I expect that this year might even improve on the last one. The Sunday markets are well patronized and there are a number of new stalls among the familiar faces.
The very dry conditions will make life difficult for a lot of miners, especially as the Emerald Shire Council has not relented on its decision not to provide the reticulated water to mining claims, but miners are a determined lot and will overcome most difficulties thrown up by bureaucracy.
Our mining operations
Our plans to cut back our activities in order to make life easier do not seem to be working. The demand for quality natural Australian sapphires has grown to the point that, while we are prevented from actual mining by dry conditions in Central Queensland and by wet weather at Lava Plains, we are busier than ever.
We had already moved our Lava Plains mine to the new area on the east side of the Kennedy Highway and were producing very high grade blue sapphire. Just when we were considering selling the Lava Plains operation, our supervisor John Fischer moved the mining pit area and found what we believe to be some of the nicest sapphire that has ever been found anywhere in Australia. It is still mainly of smaller size, but quite the most beautiful blue.
We are also in the process of relocating our Gemfields operation from the ‘Rush’ and ‘Ricebowl’ areas at the Sapphire end, where we have mined for several years, back to the 50 acres of lease area we hold in the ‘The Scrub’ at the Rubyvale end. The Scrub area is famous for its larger and most beautiful blue and particolor stones and was one of the first areas to be worked by the machine miners. We have hung on to this area, waiting for the market conditions to support the increased costs resulting from the more difficult treatment process, and the lower amount of sapphire recovered from the very clay-bound wash.
While the ‘Rush’ and ‘Ricebowl’ areas produce a greater amount of sapphire, it is mostly of a quality more suited to the ‘commercial’ trade end and, as such, was largely sold to visiting Asian buyers. Since the visits of the Asian buyers have all but stopped, our business is now based on the supply of high quality cut sapphires to Australian jewelers, and we hope that the move back to the Scrub area will enable us to produce larger, top grade material, albeit in smaller quantities.
We will offer our 200 acres of leases, plant and plantsite at the Sapphire end for sale. While they no longer form part of our planned operation, they remain a valuable commodity for anyone who has a need for proven larger, efficient treatment system to produce the commercial sapphire found in this area.
Gem shows and jewelry fairs
We have already attended the North Brisbane Lapidary Club show, the Brisbane JAA Jewelry Fair and the Australian Gemboree, which was held at Gatton this year. All these shows were excellent, both in their organizational aspects and in the commercial returns achieved.
It appears to me that, for the last few years, many discerning buyers have been aware that the sale of faked gemstone material, whether it be synthetic, dyed, chemically treated, irradiated or whatever, has largely been undisclosed, and they have lacked the confidence to buy.
Many trade people were also content to buy the cheap, mostly Asian, products in the knowledge that they could resell them at a significant profit to less discerning buyers, even though they had no idea of the true nature of the product they sold.
As a result of TV programs about problems in the jewelry industry, and with the assistance of the brochures put out by the ACCC which both reminded sellers of their responsibilities under government legislation and buyers of their rights and protection, buyers now seem to be even more aware of the adulterated gem material that is on the market, but are prepared to take the trouble to ask questions so that they can satisfy themselves that they are getting what they want—and very importantly, once satisfied, they are prepared to buy.
It was very pleasing to note that, at the shows we have attended, the true nature and treatment status of gemstones was generally clearly displayed for the customers to see, and I hope that all future shows insist on this, and monitor compliance.
There is nothing wrong with a treated or synthetic gemstone, as along as it is sold as such, and is priced accordingly. I was personally very disappointed that the show that the ‘Jewellery World’ magazine had planned for Sydney later this year is not going ahead, as many of the principles espoused by the organizers mirrored my own convictions on what is in the best interests of the genuine Australian manufacturing jewelers, in order to provide for the longevity of our Australian Gemstone and Jewellery manufacturing industries.
Website sales list
We have experienced a significant increase in the demand for significant sapphires, particularly greens, parti-colors and the rarer yellows. Many of these fancy sapphires are found in the hand mining areas and many of the hand miners have some absolutely fabulous stones, but no way to market them.
We have therefore set a system on our second website http://www.australiansapphire.com/ to allow the small scale miners and others to present their stones for sale. We intend that this service may be used for any genuine Australian gemstone, and not just sapphires. We do not collect any cut or commission from the sale of other people’s stones on this website. Any dealing is solely between the buyer and the seller.
We do require that sellers sign a declaration that all gems placed on this sale list be guaranteed to be genuine, natural gemstones of Australian origin and, as always, we recommend that buyers ask for a clearly written certificate of authenticity or similar statement signed by the seller.
Faceting courses
The faceting courses organized by the Queensland Sapphire Producers Association in conjunction with the Gemfields Lions Club and run by John Broadfoot have continued to be a great success, with every course fully subscribed, which gives hope for the continuation of the cutting of at least a portion of our production within Australia, thus retaining jobs in our own area.
There also now seems to be a growing shortage of trained jewelers, by that I mean real manufacturing jewelers, not those who just resell goods that were manufactured overseas and imported into Australia, and I hope that the people in charge of our training systems will address this problem before it too has an impact on our ability to produce genuine local products, at an affordable price, for those customers who are proud to buy Australian.
Chrysoprase
As I detailed in an earlier report, we were given the opportunity to mine and purchase a quantity of chrysoprase from the Marlborough deposit, north of Rockhampton. We have completed that mining, but we have some 50 tons of rough chrysoprase stockpiled on our Calliope cattle property.
The rough chrysoprase varies from smaller pieces to boulders of several kilos, up to a ton (or several tons), with the largest being over 16 tons. The color varies from the darker green to a bright, translucent peppermint green, to the paler colors of the parent chalcedony. We do not intend to break down the larger boulders as we believe that, in time, they will become quite valuable as major carving pieces.
We have now had time to produce a fair quantity of finished material from this stockpile, including good quality cabochons, lovely beads and some amazing carved pieces. The beads are most beautiful, and start at less than 40 cents per carat for the paler colors, but can go up to $5.00 per carat for the jade green colors.
In keeping with our philosophy on gemstones, all this material is sold as completely natural, with no treatment or dyeing whatsoever. We have also used our 24 inch slabbing saw to produce slabs which can be used for bases for clocks, desk equipment or just for the beauty of the material itself.
Our partner in the chrysoprase venture is Rick Hodel who lives in the northern suburbs of Brisbane, and is willing to visit potential clients in the south east corner of Queensland. You can contact him on: 07 3888 3280 or on mobile 0427 265 045
Black spinel
For many years, the sapphire miners have recovered a gemstone called black spinel (a.k.a pleonaste) which has always been discarded as being of too low a value to worry about. When either cabbed or faceted, polished beads or carved, this material actually produces the most beautiful gems. It is harder and more lustrous than onyx, and takes a very fine polish.
While there is currently a limited use of this material as a gemstone in its own right, it produces the most beautiful black beads, which we supply to jewelers in temporary strings in a variety of shapes and sizes, and at prices around 40 cents per carat.
Zeolite
Ad the time of last report, I mentioned that we were fattening some steers in our feedlot on our cattle property with a feed ration that included 5% zeolite powder. I can now report that these steers fattened beautifully, and we were absolutely amazed at the totally spotless condition of their livers and kidneys when they were slaughtered. For those of you who do not recognize the significance of this, it is most unusual for animals subjected to feedlot conditions not to have some form of lesions or marking of the livers and kidneys, and the condition of these organs is considered an important measure of the animal’s health.
We continue to be able to supply, at no cost, this powdered zeolite material to the many persons requesting it for personal use an aid in controlling the effects of many ailments which we understand, includes cancerous conditions and blood related disorders. We do this on firm understanding that persons requesting it do so with no assurances or guarantees, as in this country there still has not been any testing or clinical trials of this naturally occurring material, only a great deal of anecdotal evidence from people who are using it.
Hardly a day goes by without a call from someone to thank for sending them some of this powder and to tell us of benefits they have derived from its use. It is such a pity that this information is not being obtained by trained persons under controlled conditions, and subject to the strict analysis needed for its approval for medicinal use.
We understand the mine which produces this material is being sold at present, and we hope that we will be able to continue obtaining powder from the new owners. We would have loved to purchase the mine ourselves, but we are trying hard to slow down, not to take on new responsibilities. We trust that you will all join us in praying for rain for all those individuals and industries so badly affected by the widespread drought, and all those of you in the flooded northern regions who are sick of rain can join and pray too for a more even distribution of this most precious commodity.
I must admit that I do not entirely agree with the current politically popular theory that this drought is all due to man-induced global warming. Our rough sapphire at Lava Plains is often fractured because it was expelled into a frozen landscape during geologically recent ice age, so there has been a bit of warming going on for several thousand years, and there have been many droughts as serious as the one we are now experiencing.
I think that, to a large extent, the politicians of all colors, State and Federal, are desperately trying to cover their backsides for their failure to take any positive action on either construction of new dams or more importantly on better use by industry of recycled water to minimize the amount of new water required by the reticulation systems in our cities.
It would appear to be commonsense that the first priority would be to ensure the efficient utilization of every drop of water pumped out of the storages, and that it should not be necessary to even consider the use of treated water for human consumption until there is 100% use of recycled water by industry and on parks and gardens, sporting ovals etc.
People in towns and cities in our area have been discouraged for years from having domestic water tanks, despite the fact that many of us in more remote areas have learned to live solely on the water we collect in them. Now the same councils and governments are falling over themselves trying to promote such obvious measures.
I’m sorry for the lecture, but we seem to be governed by blind idiots, but then again, it may just be that I am trying not to sound too cynical about their ultimate agendas.
Monday, June 11, 2007
About China's Gold Production
(via Reuters) It has been reported that China, the world's third largest gold producer will become the second largest producer of gold in 2007.
The real story @ http://in.news.yahoo.com/070608/137/6gscn.html
The real story @ http://in.news.yahoo.com/070608/137/6gscn.html
The Challenges And Opportunities Of Growing And Marketing South Sea Cultured Pearls
Nicholas Paspaley (Executive Chairman, Paspaley Pearling Company Pty Ltd, Australia) writes:
Over the last 50 years, the cultured pearl industry has undergone a significant transformation. It has changed from a period when Japanese and (later) South Sea cultured pearls were effectively the only cultured pearls in the marketplace to the situation today, where there are a large variety of cultured pearls available from many different localities and of many different types.
In the pre-culturing era, all oceanic (saltwater) pearls were classified as Oriental pearls, and South Sea pearls fell into this generic category. With the advent of pearl culturing, however, pearls became more accurately known for the type of oyster that produced them and the region in which those oysters grew—hence the term South Sea pearls.
Naturally occurring pearls from the Pinctada maxima oyster native to the South Seas have been traded for thousands of years. But in past centuries, many natural South Sea pearls were undoubtedly traded simply as Gulf pearls. Because of its spectacular nacre, the South Sea pearl oyster historically has produced some of the most significant natural pearls in the world. Therefore, it follows that this oyster ahs the ability to produce magnificent cultured pearls as well.
However, the competition for market share between gem producers as well as between different pearl types is fierce. At the same time, there are significant gaps in the expertise required to grow pearl oysters and conduct pearl farming compared to many other fields of knowledge. There are very few experts today who have a broad knowledge on a comprehensive range of pearl and pearl farming issues.
The challenge for the South Sea cultured pearl industry today is twofold: to produce pearls of a superior quality, on the basis of which they can be differentiated in the wider pearl market, and to improve the level of knowledge and understanding of pearls in the marketplace.
Useful link:
www.paspaley.com
Over the last 50 years, the cultured pearl industry has undergone a significant transformation. It has changed from a period when Japanese and (later) South Sea cultured pearls were effectively the only cultured pearls in the marketplace to the situation today, where there are a large variety of cultured pearls available from many different localities and of many different types.
In the pre-culturing era, all oceanic (saltwater) pearls were classified as Oriental pearls, and South Sea pearls fell into this generic category. With the advent of pearl culturing, however, pearls became more accurately known for the type of oyster that produced them and the region in which those oysters grew—hence the term South Sea pearls.
Naturally occurring pearls from the Pinctada maxima oyster native to the South Seas have been traded for thousands of years. But in past centuries, many natural South Sea pearls were undoubtedly traded simply as Gulf pearls. Because of its spectacular nacre, the South Sea pearl oyster historically has produced some of the most significant natural pearls in the world. Therefore, it follows that this oyster ahs the ability to produce magnificent cultured pearls as well.
However, the competition for market share between gem producers as well as between different pearl types is fierce. At the same time, there are significant gaps in the expertise required to grow pearl oysters and conduct pearl farming compared to many other fields of knowledge. There are very few experts today who have a broad knowledge on a comprehensive range of pearl and pearl farming issues.
The challenge for the South Sea cultured pearl industry today is twofold: to produce pearls of a superior quality, on the basis of which they can be differentiated in the wider pearl market, and to improve the level of knowledge and understanding of pearls in the marketplace.
Useful link:
www.paspaley.com
A Moral Dimension
I wonder how many gem and jewelry companies can survive like the TaTas + Birlas given the restructuring, merging and bankruptcies in the industry. The TaTa and Birla business success story should be a case study for any aspiring entreprenuer.
Jay Dubashi writes:
Why is it that some businesses last a long time, sometimes centuries, while some don't? Take Tatas. They are a 150-year old group and still going strong. Scores of others have come and gone, some even bigger than Tatas but they have fallen by the wayside and vanished into thin air.
Businesses are essentially money-making enterprises. Money is what keeps them going. But money is not enough, nor is it everything. Money is to business what food is to living organisms. You cannot do without food, but you have to have something more to keep you going.
That something is a moral dimension, something bigger than you, or at a level much higher than money. Without such a dimension, you are just like a pig at the trough, using the trough as a sole reason for your existence.
Ghanashyam Das Birla always said that he was not a businessman. He was actually much more than a businessman. He was a political activist all his life, intensely interested in India's struggle for freedom and supported Gandhi through all his ups and down.This at a time when the British were closely watching him. In fact, GD Birla's close association with Gandhi so alarmed his brothers that there was a move at one time to split the family business and get rid of GD. But it does not seem to have bothered him.
It was the same with Jamsetji Nusserwanji Tata. Jamsetji set up his first industry, a textile mill, immediately after the so-called Mutiny, but what he wanted to do was something much bigger - a steel plant. But the British government in India was deadly opposed to Indians musling in on their monopoly.
Jamsetji received no help at all from the Britishers, and he had to take the help of Americans for his new enterprises. The steel plant at Jamshedpur was set up in the teeth of opposition from foreign vested interests, and it was this, not money, that drove Jamsetji. Incidentally, Tata Steel will be completing its centenary this year.
There were times during the depression of the thirties when it was touch and go whether Tata Steel would survive. There was no money in the kitty and things were so bad that at one time the Tatas have almost decided to close down the factory and go into liquidation. But Jamsetji's two sons and their wives saved the day.
GD Birla was so much involved in Gandhi's politics that at one time the Britishers were seriously thinking of shutting down his jute and cotton mills and throwing him into jail. Somehow he managed to survive, though his brothers were very much cut up with him and almost disowned him.
This is what I call moral dimension, when your drive comes not from money but something bigger than money. I once spent a whole evening with GD in his Delhi residence. He was then past eighty but as perky as ever. Throughout the evening, we did not even once mention business, though it was very much on the agenda. At one point, GD said that he was not a businessman. To call GD a mere businessman is tantamount to calling Gandhi a politician. In fact, Gandhi, a baniya, was more of a businessman than Birla, which is why they got on so well.
Take it from me. Half the businesses you see today will not make it beyond the half-way mark of the 21st century, if at all. But the Tatas and Birlas will still be there, because they are not really business as you and I know them.
More info @ http://www.valueresearchonline.com/story/storyview.asp?str=10007
Jay Dubashi writes:
Why is it that some businesses last a long time, sometimes centuries, while some don't? Take Tatas. They are a 150-year old group and still going strong. Scores of others have come and gone, some even bigger than Tatas but they have fallen by the wayside and vanished into thin air.
Businesses are essentially money-making enterprises. Money is what keeps them going. But money is not enough, nor is it everything. Money is to business what food is to living organisms. You cannot do without food, but you have to have something more to keep you going.
That something is a moral dimension, something bigger than you, or at a level much higher than money. Without such a dimension, you are just like a pig at the trough, using the trough as a sole reason for your existence.
Ghanashyam Das Birla always said that he was not a businessman. He was actually much more than a businessman. He was a political activist all his life, intensely interested in India's struggle for freedom and supported Gandhi through all his ups and down.This at a time when the British were closely watching him. In fact, GD Birla's close association with Gandhi so alarmed his brothers that there was a move at one time to split the family business and get rid of GD. But it does not seem to have bothered him.
It was the same with Jamsetji Nusserwanji Tata. Jamsetji set up his first industry, a textile mill, immediately after the so-called Mutiny, but what he wanted to do was something much bigger - a steel plant. But the British government in India was deadly opposed to Indians musling in on their monopoly.
Jamsetji received no help at all from the Britishers, and he had to take the help of Americans for his new enterprises. The steel plant at Jamshedpur was set up in the teeth of opposition from foreign vested interests, and it was this, not money, that drove Jamsetji. Incidentally, Tata Steel will be completing its centenary this year.
There were times during the depression of the thirties when it was touch and go whether Tata Steel would survive. There was no money in the kitty and things were so bad that at one time the Tatas have almost decided to close down the factory and go into liquidation. But Jamsetji's two sons and their wives saved the day.
GD Birla was so much involved in Gandhi's politics that at one time the Britishers were seriously thinking of shutting down his jute and cotton mills and throwing him into jail. Somehow he managed to survive, though his brothers were very much cut up with him and almost disowned him.
This is what I call moral dimension, when your drive comes not from money but something bigger than money. I once spent a whole evening with GD in his Delhi residence. He was then past eighty but as perky as ever. Throughout the evening, we did not even once mention business, though it was very much on the agenda. At one point, GD said that he was not a businessman. To call GD a mere businessman is tantamount to calling Gandhi a politician. In fact, Gandhi, a baniya, was more of a businessman than Birla, which is why they got on so well.
Take it from me. Half the businesses you see today will not make it beyond the half-way mark of the 21st century, if at all. But the Tatas and Birlas will still be there, because they are not really business as you and I know them.
More info @ http://www.valueresearchonline.com/story/storyview.asp?str=10007
De Beers Plans Massive Restructuring of Diamdel
Chaim Even-Zohar writes about De Beers restructuring + the Diamdel story, its past and present status @
http://www.idexonline.com/portal_FullEditorial.asp?TextSearch=&KeyMatch=0&id=27378
http://www.idexonline.com/portal_FullEditorial.asp?TextSearch=&KeyMatch=0&id=27378
Sunday, June 10, 2007
PearlParadise.com President Buys Chinese Akoya Pearl Farm
Jeremy Shepherd, president of PearlParadise.com says he has become the first American to own an Akoya pearl farm in Asia.
More info @ http://www.jckonline.com/article/CA6450060.html?industryid=46016
More info @ http://www.jckonline.com/article/CA6450060.html?industryid=46016
Apollo – the World’s Only Everlasting Diamond Mine
Chaim Even-Zohar writes about the scientists and the marketing people behind Apollo, a perpetual diamond mine, with a mining life that lasts forever, something no natural diamond mine can claim @ http://www.idexonline.com/portal_FullEditorial.asp?TextSearch=&KeyMatch=0&id=27340
Useful link:
www.apollodiamond.com
Useful link:
www.apollodiamond.com
Identifying Treated And Synthetic Gems: The Dealer’s Perspective
Robert Kane is a former staff of GIA and now a fine gemstone dealer. His views are valid today because today it's ninety five situaion: Transalation = ninety five percent of the dealers in the industry are not properly trained; only five percent is properly trained and continuously keep learning by taking refresher courses + attending seminars + workshops on new treatments, synthetics, imitations and new gem varieties. The amazing thing is most gem dealers are of the illusion that they don't need training; they are already successful by their own virtue, luck, connections, money + they think they know more about gemstones than a gemologist. The world has changed so dramatically that if you are living in the US or Europe you must always watch your back with plan B, C, or D because you don't want to get into legal problems, while in Asia, Africa and South America there are no binding consumer protection laws; at times it's like two blind walking the streeet situation. Buyer beware!
Robert Kane (President/CEO, Fine Gems International, USA) writes:
In gem treatments and synthetics, there have been more developments in the last 10 years than in the previous 50 combined. Since the 1999 Symposium, we have seen, for example, the commercial availability of (1) HPHT-treated diamonds in a variety of colors, (2) various colors of faceted synthetic gem-quality diamonds, (3) beryllium-diffused corundum, (4) poor-quality opaque corundum that has been transformed into transparent red gems by filling fractures with high-lead-content glass, and (5) diffusion ruby, which proved to be synthetic ruby overgrowth on natural corundum. It is critical that we identify and disclose these products if we are to maintain consumer confidence.
Although most of these treatments and synthetics are based on sophisticated technology, many can still be detected through precise gemological testing and observation. And when routine testing does not yield a definitive identification, major gemological laboratories can identify nearly all of them using advanced instrumentation. This presentation discusses approaches that members of the industry can take to deal with the constant influx of these new materials.
When examining a gem, the experienced gemologist systematically rules out the treatments and synthetics known for that particular stone. By running through a list of possibilities and how they are identified, one can identify the gem in question using standard observation and testing, or make an informed decision on a proper course of action, such as submitting the gemstone to an internationally respected gem laboratory for testing. The challenge is to recognize when the identification is beyond your knowledge level—to know when you don’t know.
By not facing these difficult issues, and thus buying and selling blindly, you open yourself and your company up to loss of reputation and to liability that could result in financial loss.
Gem Identify Assurance Program
One way to address these identification challenges is to develop a gem identity assurance program for your company based on gemological knowledge, trust in your suppliers, security through lab reports, and determining the level or risk that is acceptable in a given situation.
Gemological knowledge
Decades of scientific research by groups such as De Beers, GIA, and others have provided practical solutions to identification problems created by the proliferation of treated and synthetic gems. You can—and should—take advantage of this information by (1) regularly reading the gemological journals; (2) attending seminars held during trade shows such as at Tucson, Las Vegas, Basel, Bangkok, and Hong Kong; (3) taking specialized training at laboratories such as SSEF and AGTA; and (4) availing yourself of resources such as the De Beers CD-ROM Diamonds and books on specific topics—for example, GIA’s Gems & Gemology in Review: Synthetic Diamonds. There are also many educational programs available around the world to fit most needs.
There is no substitute for up-to-date gemological knowledge and solid experience. To this end, you should also consider purchasing your own gem-testing equipment, a portable lab, or-depending on your circumstances—a complete advanced gem testing laboratory.
Trust in your suppliers and financial resources
It is very important to buy gems from a trusted and knowledgeable supplier—one who will refund your money if testing reveals that the gem is not what it was represented to be. Always demand full disclosure regarding treatments and synthetics in writing on the invoice—if the seller will not comply, then find a new supplier. Buy from companies that belong to organizations such as ICA (International Colored Stone Association), AGTA (American Gem Trade Association), AGS (American Gem Society), TGJTA (Thai Gem & Jewelry Traders Association), WFDB (World Federation of Diamond Bourses), and the like. Members of such organizations must adhere to rules of ethical behavior, and the organizations can and will issue sanctions if these rules are violated.
Security through laboratory reports
Establish a company policy whereby all gems over a certain monetary value, or certain kinds of gemstones, must have a report from an internationally recognized gem lab. On expensive gems, obtain reports from at least two different labs. This is particularly important when geographic locality reports are required (because these determinations are not an exact science, the second lab may indicate a different origin, which case a third report is needed). Lab reports help protect you from future liability problems with your clients.
Risk tolerance
Determine what level of risk is acceptable. Certainly, the buying and selling of a 1ct purplish red diamond warrants an updated GIA lab report. Yet it may be reasonable to accept the word of your supplier (who knows the chain of custody and guarantees it in writing) when purchasing small amethysts, various colors of small sapphires, or parcels of emerald melee. Although you do run some risk that a mistake has been made, for most dealers the risk is manageable. Again, though, this depends on the specific situation. If a parcel of 2.0mm yellow sapphires are going into an expensive piece of jewelry featuring 200 such stones, testing (or at least spot-testing) would be required to ensure accurate representation of the entire piece.
Buying and Testing scenarios
Following are two examples of buying and testing situations.
Scenario 1
A large blue (synthetic) sapphire
A dealer is offered an 8ct superbly cut, clean, intense blue sapphire—set in an antique mounting—for $10000. However, it is not accompanied by a lab report. During very careful examination with a darkfield binocular microscope and diffused lighting, she sees subtle curved color zoning—proving that what appeared to be a magnificent natural gem was actually a flame-fusion or Verneuil synthetic sapphire. In 2005, a natural-color Sri Lankan sapphire of this size and apparent quality sold for $30000; a comparable Burmese sapphire sold for $55000. If it seems too good to be true, it probably is.
Scenario 2
A 3+ ct Unheated Mogok ruby
One gem dealer offers another a 3+ carat ruby, accompanied by a report from a gem testing stating: Burma, no indication of thermal treatment. Microscopic examination revealed inclusions characteristic of untreated Mogok rubies, such as unaltered rutile needles and small calcite crystals. It also revealed a small fracture extending from the crown facets toward the girdle. The second dealer’s prospective buyer was willing to pay in excess of $100000 for the stone, but wanted a report from a certain US laboratory. That lab reported evidence of clarity enhancement—specifically, foreign material filling the surface reaching fracture, which is typically done in an attempt to reduce the fracture’s visibility. After the stone was soaked in acetone for several days (with the first dealer’s permission), the filler was no longer present, causing the fracture to become more prominent. The client was no longer interested in the ruby, and the gem dealer lost the sale. As mentioned above, with high value gems it is good to obtain reports from two different laboratories.
Navigating the challenges ahead
To maintain vitality and confidence in our industry, it is critical that we stay up to date on technological developments in gem synthesis, treatment, and identification. Learn what is in the market, how to identify it, and when to refer a gem to a recognized laboratory for advanced analytical testing. Buy from a trusted and experienced source. With expensive gems, this can be backed up by laboratory reports. The rapid advances in technology will inevitably bring challenges to the gem and jewelry industry—some will present positive opportunities, while many others will create daunting gem identification issues. Vigilance in pursuing knowledge will insure that our industry continues to flourish.
Robert Kane (President/CEO, Fine Gems International, USA) writes:
In gem treatments and synthetics, there have been more developments in the last 10 years than in the previous 50 combined. Since the 1999 Symposium, we have seen, for example, the commercial availability of (1) HPHT-treated diamonds in a variety of colors, (2) various colors of faceted synthetic gem-quality diamonds, (3) beryllium-diffused corundum, (4) poor-quality opaque corundum that has been transformed into transparent red gems by filling fractures with high-lead-content glass, and (5) diffusion ruby, which proved to be synthetic ruby overgrowth on natural corundum. It is critical that we identify and disclose these products if we are to maintain consumer confidence.
Although most of these treatments and synthetics are based on sophisticated technology, many can still be detected through precise gemological testing and observation. And when routine testing does not yield a definitive identification, major gemological laboratories can identify nearly all of them using advanced instrumentation. This presentation discusses approaches that members of the industry can take to deal with the constant influx of these new materials.
When examining a gem, the experienced gemologist systematically rules out the treatments and synthetics known for that particular stone. By running through a list of possibilities and how they are identified, one can identify the gem in question using standard observation and testing, or make an informed decision on a proper course of action, such as submitting the gemstone to an internationally respected gem laboratory for testing. The challenge is to recognize when the identification is beyond your knowledge level—to know when you don’t know.
By not facing these difficult issues, and thus buying and selling blindly, you open yourself and your company up to loss of reputation and to liability that could result in financial loss.
Gem Identify Assurance Program
One way to address these identification challenges is to develop a gem identity assurance program for your company based on gemological knowledge, trust in your suppliers, security through lab reports, and determining the level or risk that is acceptable in a given situation.
Gemological knowledge
Decades of scientific research by groups such as De Beers, GIA, and others have provided practical solutions to identification problems created by the proliferation of treated and synthetic gems. You can—and should—take advantage of this information by (1) regularly reading the gemological journals; (2) attending seminars held during trade shows such as at Tucson, Las Vegas, Basel, Bangkok, and Hong Kong; (3) taking specialized training at laboratories such as SSEF and AGTA; and (4) availing yourself of resources such as the De Beers CD-ROM Diamonds and books on specific topics—for example, GIA’s Gems & Gemology in Review: Synthetic Diamonds. There are also many educational programs available around the world to fit most needs.
There is no substitute for up-to-date gemological knowledge and solid experience. To this end, you should also consider purchasing your own gem-testing equipment, a portable lab, or-depending on your circumstances—a complete advanced gem testing laboratory.
Trust in your suppliers and financial resources
It is very important to buy gems from a trusted and knowledgeable supplier—one who will refund your money if testing reveals that the gem is not what it was represented to be. Always demand full disclosure regarding treatments and synthetics in writing on the invoice—if the seller will not comply, then find a new supplier. Buy from companies that belong to organizations such as ICA (International Colored Stone Association), AGTA (American Gem Trade Association), AGS (American Gem Society), TGJTA (Thai Gem & Jewelry Traders Association), WFDB (World Federation of Diamond Bourses), and the like. Members of such organizations must adhere to rules of ethical behavior, and the organizations can and will issue sanctions if these rules are violated.
Security through laboratory reports
Establish a company policy whereby all gems over a certain monetary value, or certain kinds of gemstones, must have a report from an internationally recognized gem lab. On expensive gems, obtain reports from at least two different labs. This is particularly important when geographic locality reports are required (because these determinations are not an exact science, the second lab may indicate a different origin, which case a third report is needed). Lab reports help protect you from future liability problems with your clients.
Risk tolerance
Determine what level of risk is acceptable. Certainly, the buying and selling of a 1ct purplish red diamond warrants an updated GIA lab report. Yet it may be reasonable to accept the word of your supplier (who knows the chain of custody and guarantees it in writing) when purchasing small amethysts, various colors of small sapphires, or parcels of emerald melee. Although you do run some risk that a mistake has been made, for most dealers the risk is manageable. Again, though, this depends on the specific situation. If a parcel of 2.0mm yellow sapphires are going into an expensive piece of jewelry featuring 200 such stones, testing (or at least spot-testing) would be required to ensure accurate representation of the entire piece.
Buying and Testing scenarios
Following are two examples of buying and testing situations.
Scenario 1
A large blue (synthetic) sapphire
A dealer is offered an 8ct superbly cut, clean, intense blue sapphire—set in an antique mounting—for $10000. However, it is not accompanied by a lab report. During very careful examination with a darkfield binocular microscope and diffused lighting, she sees subtle curved color zoning—proving that what appeared to be a magnificent natural gem was actually a flame-fusion or Verneuil synthetic sapphire. In 2005, a natural-color Sri Lankan sapphire of this size and apparent quality sold for $30000; a comparable Burmese sapphire sold for $55000. If it seems too good to be true, it probably is.
Scenario 2
A 3+ ct Unheated Mogok ruby
One gem dealer offers another a 3+ carat ruby, accompanied by a report from a gem testing stating: Burma, no indication of thermal treatment. Microscopic examination revealed inclusions characteristic of untreated Mogok rubies, such as unaltered rutile needles and small calcite crystals. It also revealed a small fracture extending from the crown facets toward the girdle. The second dealer’s prospective buyer was willing to pay in excess of $100000 for the stone, but wanted a report from a certain US laboratory. That lab reported evidence of clarity enhancement—specifically, foreign material filling the surface reaching fracture, which is typically done in an attempt to reduce the fracture’s visibility. After the stone was soaked in acetone for several days (with the first dealer’s permission), the filler was no longer present, causing the fracture to become more prominent. The client was no longer interested in the ruby, and the gem dealer lost the sale. As mentioned above, with high value gems it is good to obtain reports from two different laboratories.
Navigating the challenges ahead
To maintain vitality and confidence in our industry, it is critical that we stay up to date on technological developments in gem synthesis, treatment, and identification. Learn what is in the market, how to identify it, and when to refer a gem to a recognized laboratory for advanced analytical testing. Buy from a trusted and experienced source. With expensive gems, this can be backed up by laboratory reports. The rapid advances in technology will inevitably bring challenges to the gem and jewelry industry—some will present positive opportunities, while many others will create daunting gem identification issues. Vigilance in pursuing knowledge will insure that our industry continues to flourish.
Major Diamond Mines Of The World: Tectonic Location, Production, And Value
Here is an insider view on the commercially important diamond deposits around the world. Many experts believe Botswana is the Kuwait of Africa, the rising super star, with no major tribal conflicts, relatively stable government except problems related to bushmen and their habitat. Canada is a newcomer with immense opportunities and difficulties due the landscape + the weather. Russia is trying to catch-up, but the politics and their way of doing business may have a lot of surprises for the diamond world. More to come.....
A J A (Bram) Janse (Archon Exploration Pty Ltd, Perth, Western Australia) writes:
The spatial distribution of the world’s major diamond mines is intimately related to the age of the earth’s crust. According to Clifford-Janse terminology, the three age-defined tectonic crustal elements are archons, protons, and tectons. At present, all diamond mines developed on kimberlite pipes are located within the boundaries of an archon, while those developed on lamproite pipes are located on a proton. Even though only one major diamond mine is underlain by lamproite pipe (the Argyle mine in Australia), several small diamond mines on lamproite pipes and other occurrences of diamond-bearing lamproites support this view. The figure also shows that major diamond mines largely cluster into three regions of the world: southern Africa, Siberia, and western Canada.
The tabulated data show Jwaneng in Botswana has the greatest current value and very high current production, followed by Udachnaya in Siberia, Orapa in Botswana, Ekati and Diavik in Canada, and Venetia in South Africa. The Argyle mine in Australia has a high production, but a low value. The most important producers for the next decade are likely to be Jwaneng, Orapa, Ventia, and Diavik, with Jubileynaya, Nyurba (Russia), Catoca (Angola), and Murowa (Zimbabwe) having slightly less importance. Argyle will continue to produce large quantities of near-gem material. The monetary values for the top six mines are in the same league as a major gold mine or a medium-sized oil field.
Date were also tabulated for seven advanced projects for which production is planned in the near future (although Jericho already commenced production in the first quarter of 2006, it is a small mine compared to Snap Lake). Victor is also small, but it has an extraordinary high value. Gahcho Kue is currently only a resource, not yet a proven reserve and only indicated reserves are available. Camafuca is an elongated pipe or the fusion of five pipes in a line underneath the bed of the Chicapa River, and it will be first operated by a five year dredging program.
The major mines of the future are Arkhangelskaya and Grib (both in Russia), but Grib’s opening is hampered by litigation. The Arkhangelskaya pipe will be the first of the Lomonosov cluster of five pipes to open in 2007.
A J A (Bram) Janse (Archon Exploration Pty Ltd, Perth, Western Australia) writes:
The spatial distribution of the world’s major diamond mines is intimately related to the age of the earth’s crust. According to Clifford-Janse terminology, the three age-defined tectonic crustal elements are archons, protons, and tectons. At present, all diamond mines developed on kimberlite pipes are located within the boundaries of an archon, while those developed on lamproite pipes are located on a proton. Even though only one major diamond mine is underlain by lamproite pipe (the Argyle mine in Australia), several small diamond mines on lamproite pipes and other occurrences of diamond-bearing lamproites support this view. The figure also shows that major diamond mines largely cluster into three regions of the world: southern Africa, Siberia, and western Canada.
The tabulated data show Jwaneng in Botswana has the greatest current value and very high current production, followed by Udachnaya in Siberia, Orapa in Botswana, Ekati and Diavik in Canada, and Venetia in South Africa. The Argyle mine in Australia has a high production, but a low value. The most important producers for the next decade are likely to be Jwaneng, Orapa, Ventia, and Diavik, with Jubileynaya, Nyurba (Russia), Catoca (Angola), and Murowa (Zimbabwe) having slightly less importance. Argyle will continue to produce large quantities of near-gem material. The monetary values for the top six mines are in the same league as a major gold mine or a medium-sized oil field.
Date were also tabulated for seven advanced projects for which production is planned in the near future (although Jericho already commenced production in the first quarter of 2006, it is a small mine compared to Snap Lake). Victor is also small, but it has an extraordinary high value. Gahcho Kue is currently only a resource, not yet a proven reserve and only indicated reserves are available. Camafuca is an elongated pipe or the fusion of five pipes in a line underneath the bed of the Chicapa River, and it will be first operated by a five year dredging program.
The major mines of the future are Arkhangelskaya and Grib (both in Russia), but Grib’s opening is hampered by litigation. The Arkhangelskaya pipe will be the first of the Lomonosov cluster of five pipes to open in 2007.
New Localities In Madagascar
Federico Pezzotta is an expert on Madagascar, and pezzottaite is named after him. The author also provides the geological landscape + the unique particularities of the gem deposits in Madagascar. Many experts believe Madagascar is vast with poor infrastructure + a virgin territory + there may be more surprises from from this island. Keep in touch.
Federico Pezzotta (Natural History Museum, Milan, Italy) writes:
Madagascar is host to an abundance and variety of gem materials as a result of its long and complex geologic history. The upper Archean to Neoproterozoic crystalline basement of Madagascar experienced locally unusual and even unique geologic conditions during several mountain-building events. Erosion of these rocks occurred during the late to post-tectonic uplift of the basement, and deposited Permian-Mesozoic sediments along the western margin of the Mozambique basin, locally forming immense paleoplacer deposits (e.g Ilakaka). More recently, the morphologic and climatic conditions of the island during the past few million years resulted in the formation of abundant secondary residual and alluvial gem deposits.
Even though research and mining of Madagascar’s gems has continued for more than a century, many large areas in the island remain poorly explored and have significant potential for the discovery of new deposits. Within the last few years, the country’s improved political situation has allowed for important developments in the scientific research, mining, and trading of gems.
Recently, two major discoveries occurred in Madagascar, both in Fianarantosa Province: (1) a series of multicolored tourmaline deposits, of both primary and residual nature, in a large area between the villages of Ambatofitorahana and Ambohimasoa, along the national road connecting the towns of Ambositra and Fianarantosoa; and (2) a multicolored sapphire deposit of residual nature located 17km south of the village of Ranotsara, southeast of the town of Ihosy.
The tourmaline deposits are related to a large rare-element miarolitic pegmatite field, surprisingly rather undocumented in the available geologic maps, that extends in a northeast-southwest direction for a distance of ~40km. Initial discoveries of tourmaline in the area were made in 1995-1996 with the mining of the primary and secondary residual deposits of Valozoro, a few kilometers southeast of Ambatofitorahana. No additional significant discoveries were made until August-September 2005 when, in the Anjoma area (located a few kilometers southwest of Ambatofitorahana), an enormous quantity of multicolored tourmaline (weighing several tones, but mainly of carving quality) was found close to the surface at Anjomanandihizna (also known as Nandihizana). Soon afterward, additional multicolored tourmaline deposits were discovered south of this area; the most important ones at Fiadanana (a few kilometers south of Valozoro), Ankitsikitsika (about 15 km south of Anjomanandihizana), and Antsengy (northwest of the village of Ambohimahasoa). Local gem dealers refer to this entire area as Camp Robin, from the name of a village in center of the district in which much of the gem trading occurs.
The new sapphire deposit, named Marosely, was discovered in October 2005. Transparent bipyramidal sapphire crystals, with colors ranging from blue to purple and, rarely, purplish red (ruby), have been recovered mainly in small size (less than 0.4 g). Larger crystals of gem quality are rare, but occasionally they exceed 2 g and produce good size cut stones. These crystals originated from the high grade metamorphic bedrock, and were concentrated in near-surface residual deposits through erosion. The total production of sapphire rough from Marosely, through June 2006 is estimated at about 500 kg.
Federico Pezzotta (Natural History Museum, Milan, Italy) writes:
Madagascar is host to an abundance and variety of gem materials as a result of its long and complex geologic history. The upper Archean to Neoproterozoic crystalline basement of Madagascar experienced locally unusual and even unique geologic conditions during several mountain-building events. Erosion of these rocks occurred during the late to post-tectonic uplift of the basement, and deposited Permian-Mesozoic sediments along the western margin of the Mozambique basin, locally forming immense paleoplacer deposits (e.g Ilakaka). More recently, the morphologic and climatic conditions of the island during the past few million years resulted in the formation of abundant secondary residual and alluvial gem deposits.
Even though research and mining of Madagascar’s gems has continued for more than a century, many large areas in the island remain poorly explored and have significant potential for the discovery of new deposits. Within the last few years, the country’s improved political situation has allowed for important developments in the scientific research, mining, and trading of gems.
Recently, two major discoveries occurred in Madagascar, both in Fianarantosa Province: (1) a series of multicolored tourmaline deposits, of both primary and residual nature, in a large area between the villages of Ambatofitorahana and Ambohimasoa, along the national road connecting the towns of Ambositra and Fianarantosoa; and (2) a multicolored sapphire deposit of residual nature located 17km south of the village of Ranotsara, southeast of the town of Ihosy.
The tourmaline deposits are related to a large rare-element miarolitic pegmatite field, surprisingly rather undocumented in the available geologic maps, that extends in a northeast-southwest direction for a distance of ~40km. Initial discoveries of tourmaline in the area were made in 1995-1996 with the mining of the primary and secondary residual deposits of Valozoro, a few kilometers southeast of Ambatofitorahana. No additional significant discoveries were made until August-September 2005 when, in the Anjoma area (located a few kilometers southwest of Ambatofitorahana), an enormous quantity of multicolored tourmaline (weighing several tones, but mainly of carving quality) was found close to the surface at Anjomanandihizna (also known as Nandihizana). Soon afterward, additional multicolored tourmaline deposits were discovered south of this area; the most important ones at Fiadanana (a few kilometers south of Valozoro), Ankitsikitsika (about 15 km south of Anjomanandihizana), and Antsengy (northwest of the village of Ambohimahasoa). Local gem dealers refer to this entire area as Camp Robin, from the name of a village in center of the district in which much of the gem trading occurs.
The new sapphire deposit, named Marosely, was discovered in October 2005. Transparent bipyramidal sapphire crystals, with colors ranging from blue to purple and, rarely, purplish red (ruby), have been recovered mainly in small size (less than 0.4 g). Larger crystals of gem quality are rare, but occasionally they exceed 2 g and produce good size cut stones. These crystals originated from the high grade metamorphic bedrock, and were concentrated in near-surface residual deposits through erosion. The total production of sapphire rough from Marosely, through June 2006 is estimated at about 500 kg.
Saturday, June 09, 2007
More On The Black Swan Concept
(via Emergic) The Guardian wrote about Nassim Taleb’s “The BlackSwan”.
“If you are aware of your own ignorance, though, you can use it to make money, as Taleb did on Wall Street, as an options trader. Options are gambles about what the market will do. To sell an option to somebody else, you need to be confident you have some kind of theory about what will happen in the future. If you're right, you make a small amount of money; if you're wrong, you lose lots. Taleb, however, realized he had no theories. So he exploited everyone else's confidence, buying options according to no particular prediction. Most days, his rivals made a small amount of money, and he lost a small amount. But the one thing he could predict was that, if he waited long enough, something unpredictable would happen. When it did, some of his rivals would lose millions, and Taleb would make millions. It happened often enough for him to turn a big profit. It takes a rebellious nature, and an iron stomach, to go against the flow for so long. It is, perhaps, the kind of mindset that comes naturally to someone who lived through the Lebanese civil war - a classic, unpredictable black swan - and then found himself living as an exile, at one remove from American society. We are not all so good at resisting the herd's way of thinking.”
Bloomberg wrote:
There's an investment strategy to profit from improbability. “Be as hyper-conservative and hyper-aggressive as you can instead of being mildly aggressive or conservative,'' Taleb advises. “Instead of having medium risk, you have high risk on one side and no risk on the other. The average will be medium risk but constitutes a positive exposure to the Black Swan.''
The hand can feed the turkey for 1,000 days until, on day 1,001; it wrings the fowl's neck for Thanksgiving. The trick is to be the butcher, not the turkey.
“A thousand days cannot prove you right, but one day can prove you to be wrong,'' writes Taleb. “I am not urging you to stop being a fool. Just be a fool in the right places.''
With risk measures at or near record lows, including volatility indexes, corporate bond defaults, credit spreads and emerging-market yields, Taleb might help you dodge the next Black Swan.
Business Week wrote:
The Black Swan is not as unprecedented as Taleb claims. You may have encountered pieces of his arguments in recent popular books by the likes of Chris Anderson, James Gleick, Paul Ormerod, Duncan Watts, Steven Strogatz, Aaron Brown, and one of Taleb's few living heroes, Benoit Mandelbrot.
Moreover, despite Taleb's best efforts to make The Black Swan a useful guide to life, we human beings aren't wired to cope well with radical uncertainty. Donald Rumsfeld, the former Defense Secretary, famously cogitated in front of the microphones about "unknown unknowns," which is precisely Taleb's concept—and look where the philosophizing got him. Still, The Black Swan is a richly enjoyable read with an important message.
Nassim Taleb’s “The Black Swan” is one of the best and most important books you will read. Go get it!
“If you are aware of your own ignorance, though, you can use it to make money, as Taleb did on Wall Street, as an options trader. Options are gambles about what the market will do. To sell an option to somebody else, you need to be confident you have some kind of theory about what will happen in the future. If you're right, you make a small amount of money; if you're wrong, you lose lots. Taleb, however, realized he had no theories. So he exploited everyone else's confidence, buying options according to no particular prediction. Most days, his rivals made a small amount of money, and he lost a small amount. But the one thing he could predict was that, if he waited long enough, something unpredictable would happen. When it did, some of his rivals would lose millions, and Taleb would make millions. It happened often enough for him to turn a big profit. It takes a rebellious nature, and an iron stomach, to go against the flow for so long. It is, perhaps, the kind of mindset that comes naturally to someone who lived through the Lebanese civil war - a classic, unpredictable black swan - and then found himself living as an exile, at one remove from American society. We are not all so good at resisting the herd's way of thinking.”
Bloomberg wrote:
There's an investment strategy to profit from improbability. “Be as hyper-conservative and hyper-aggressive as you can instead of being mildly aggressive or conservative,'' Taleb advises. “Instead of having medium risk, you have high risk on one side and no risk on the other. The average will be medium risk but constitutes a positive exposure to the Black Swan.''
The hand can feed the turkey for 1,000 days until, on day 1,001; it wrings the fowl's neck for Thanksgiving. The trick is to be the butcher, not the turkey.
“A thousand days cannot prove you right, but one day can prove you to be wrong,'' writes Taleb. “I am not urging you to stop being a fool. Just be a fool in the right places.''
With risk measures at or near record lows, including volatility indexes, corporate bond defaults, credit spreads and emerging-market yields, Taleb might help you dodge the next Black Swan.
Business Week wrote:
The Black Swan is not as unprecedented as Taleb claims. You may have encountered pieces of his arguments in recent popular books by the likes of Chris Anderson, James Gleick, Paul Ormerod, Duncan Watts, Steven Strogatz, Aaron Brown, and one of Taleb's few living heroes, Benoit Mandelbrot.
Moreover, despite Taleb's best efforts to make The Black Swan a useful guide to life, we human beings aren't wired to cope well with radical uncertainty. Donald Rumsfeld, the former Defense Secretary, famously cogitated in front of the microphones about "unknown unknowns," which is precisely Taleb's concept—and look where the philosophizing got him. Still, The Black Swan is a richly enjoyable read with an important message.
Nassim Taleb’s “The Black Swan” is one of the best and most important books you will read. Go get it!
World's Largest Available Natural Pearl To Be Auctioned
The 575 carat pearl from 12th century Mongolia was formerly owned by Chinese emperors, Persian kings, the grandson of Genghis Khan and Marco Polo. It will be up for bidding in Abu Dhabi's Emirates Palace and on the Internet, where it is estimated to raise up to US$8 million (EUR5.89 million). The real story (via AP) @ http://english.pravda.ru/news/society/02-05-2007/90823-largest_pearl-0
Prediction: DTC to send formal Sightholder Termination Notices to All 93 Clients
Chaim Even-Zohar writes about the status of new DTC (Diamond Trading Company) sightholders + existing contracts + the uncertainities @ http://www.idexonline.com/portal_FullEditorial.asp?TextSearch=&KeyMatch=0&id=27309
Geology Of Placer Gem Deposits
Here is an experts view on placer deposits and its commercial significance in gem producing countries around the world + the geological and gemological characteristics that are important in identifying the particularities of placer deposits.
James M Prudden (Prudden GeoScience Services, Nevada, USA) writes:
Placer gem depositional environments consist of colluvial, fluvial, and beach deposits. The weathering of primary gem-bearing deposits forms overlying eluvial deposits, and the down-slope migration of the residual gems by both gravity and water creates colluvial deposits. Fluvial systems range from youthful through mature and old-age sedimentological regimes with associated channel geometrics that determine the hydraulic energy and therefore the locations of gem deposition. Fluvial systems commence with straight steep-channel gradients, with low depth-to width ratios containing unsorted clasts and large gems. This evolves into to the downstream, low-energy, old-age fluvial systems with low channel gradients that host bedded, well-sorted smaller clasts deposited in a meandering fashion within a broad flood plane. Gems in this environment are smaller and more rounded. At the point where the river enters a marine or lacustrine environment, the resulting abrupt gradient change is very favorable for gem deposition. Wave energy and long shore currents further winnow and transport gems in beach environments. Alpine and continental glaciers are nature’s bulldozers and the braded fluvial streams that are fed from their melt water effectively concentrate the contained gems from the glacial rubble.
Gem characteristics such as specific gravity, hardness, shape and durability will influence their related depositional environments and survivability, thus favoring the economic concentrations of certain gems in the fluvial milling environment.
Select case histories of a variety of placer deposits illustrate the practicality of applying detailed geology and sedimentology to placer gem exploration:
1. Australian Tertiary modified paleo-colluvial type sapphire deposits, derived from the weathering of alkaline basalts, have been a major global source of sapphires.
2. Namibian long-shore diamond distribution along the Atlantic Ocean coast constitutes the world’s most valuable diamond deposit, extending westward 100km to the continental shelf edge and 200km northward. The diamonds were originally liberated from the South African kimberlites (and possibly more distant sources) by post-Gondawana erosion of the southern African craton, which commenced in the humid Middle Cretaceous with the formation of the ancient Karoo and Kalahari Rivers. Subsequent erosion of these diamondiferous placers was accomplished by the Orange River in the Miocene. Prolonged winnowing of the diamonds increased their value by about 500%.
3. Fluvial reworking of glacial sediments in British Colombia, Canada, concentrated sapphires and garnets from several cubic kilometers of glacial material.
4. A fluvial diamond deposit in China’s Hunan province was deposited on completely weathered karst bedrock, which presents challenges to sampling and mining.
James M Prudden (Prudden GeoScience Services, Nevada, USA) writes:
Placer gem depositional environments consist of colluvial, fluvial, and beach deposits. The weathering of primary gem-bearing deposits forms overlying eluvial deposits, and the down-slope migration of the residual gems by both gravity and water creates colluvial deposits. Fluvial systems range from youthful through mature and old-age sedimentological regimes with associated channel geometrics that determine the hydraulic energy and therefore the locations of gem deposition. Fluvial systems commence with straight steep-channel gradients, with low depth-to width ratios containing unsorted clasts and large gems. This evolves into to the downstream, low-energy, old-age fluvial systems with low channel gradients that host bedded, well-sorted smaller clasts deposited in a meandering fashion within a broad flood plane. Gems in this environment are smaller and more rounded. At the point where the river enters a marine or lacustrine environment, the resulting abrupt gradient change is very favorable for gem deposition. Wave energy and long shore currents further winnow and transport gems in beach environments. Alpine and continental glaciers are nature’s bulldozers and the braded fluvial streams that are fed from their melt water effectively concentrate the contained gems from the glacial rubble.
Gem characteristics such as specific gravity, hardness, shape and durability will influence their related depositional environments and survivability, thus favoring the economic concentrations of certain gems in the fluvial milling environment.
Select case histories of a variety of placer deposits illustrate the practicality of applying detailed geology and sedimentology to placer gem exploration:
1. Australian Tertiary modified paleo-colluvial type sapphire deposits, derived from the weathering of alkaline basalts, have been a major global source of sapphires.
2. Namibian long-shore diamond distribution along the Atlantic Ocean coast constitutes the world’s most valuable diamond deposit, extending westward 100km to the continental shelf edge and 200km northward. The diamonds were originally liberated from the South African kimberlites (and possibly more distant sources) by post-Gondawana erosion of the southern African craton, which commenced in the humid Middle Cretaceous with the formation of the ancient Karoo and Kalahari Rivers. Subsequent erosion of these diamondiferous placers was accomplished by the Orange River in the Miocene. Prolonged winnowing of the diamonds increased their value by about 500%.
3. Fluvial reworking of glacial sediments in British Colombia, Canada, concentrated sapphires and garnets from several cubic kilometers of glacial material.
4. A fluvial diamond deposit in China’s Hunan province was deposited on completely weathered karst bedrock, which presents challenges to sampling and mining.
Role Of Beryllium In The Coloration Of Fe and Cr-doped Synthetic Corundum
Thailand is perceived as one of the gemstone refineries of the world. The experts from GIT shares their opinion (s) on the pros and cons of beryllium treatment in natural and synthetic corundum.
Visut Pisutha Arnond, Tobias Hager, Pornsawat Wathankul, Wilawan Atichat, Jitrin Nattachai, Chakkaphant Sutthirat, and Bootawee Sriprasert writes:
X-radiation and Be-diffusion heating experiments were performed on an iron-doped (colorless) synthetic corundum and a chromium-doped (pink) synthetic corundum to evaluate the role of beryllium in causing color in the Be-Fe-Al2O3 and Be-Cr-Al2O3 systems.
The iron-doped corundum, containing around 140-170 ppm by weight of Fe with negligible concentrations of other trace elements, was irradiated with X-rays (60 kV, 53 mA) for 30 minutes, then the color was faded for one hour with a 100-watt light bulb, and finally the sample was heat treated in a crucible with ground chrysoberyl in an electric furnace at 1780ºC in an oxidizing atmosphere for 50 hours. The chromium-doped corundum, containing around 160-210 ppm by weight of Cr with negligible concentrations of other trace elements, was also irradiated with X-rays (80 kV, 4mA) for 4 hours, then faded for 4 hours with a 100-watt light bulb, and subsequently heat treated with ground chrysoberyl at unspecified conditions by a Thai treater. At each stage of the experiments, the samples were photographed and UV-Vis absorption spectra were recorded.
Both the irradiation and Be-diffusion experiments on the iron-doped synthetic corundum created defect centers that had similar UV-Vis absorption curves and produced yellow coloration. The yellow color was unstable when induced by irradiation, but was stable after Be-diffusion.
Experiments on the chromium-doped synthetic corundum produced orange coloration (and similar UV-Vis absorption patterns) by both irradiation and Be-diffusion heating methods. Again, the orange color was unstable when induced by irradiation (and quickly faded to pink), but remained stable after Be-diffusion. These results confirm that divalent Be acts as a stabilizer of defect centers or color centers in iron-doped and chromium-doped synthetic corundum. Hence, the spectrum produced by the irradiation of Fe-doped or Cr-doped synthetic corundum was attributed to metal-related unstable color centers, while that produced in synthetic corundum doped with Be + Fe + or Be + Cr was caused by Be²+ + metal-related stable color centers.
Visut Pisutha Arnond, Tobias Hager, Pornsawat Wathankul, Wilawan Atichat, Jitrin Nattachai, Chakkaphant Sutthirat, and Bootawee Sriprasert writes:
X-radiation and Be-diffusion heating experiments were performed on an iron-doped (colorless) synthetic corundum and a chromium-doped (pink) synthetic corundum to evaluate the role of beryllium in causing color in the Be-Fe-Al2O3 and Be-Cr-Al2O3 systems.
The iron-doped corundum, containing around 140-170 ppm by weight of Fe with negligible concentrations of other trace elements, was irradiated with X-rays (60 kV, 53 mA) for 30 minutes, then the color was faded for one hour with a 100-watt light bulb, and finally the sample was heat treated in a crucible with ground chrysoberyl in an electric furnace at 1780ºC in an oxidizing atmosphere for 50 hours. The chromium-doped corundum, containing around 160-210 ppm by weight of Cr with negligible concentrations of other trace elements, was also irradiated with X-rays (80 kV, 4mA) for 4 hours, then faded for 4 hours with a 100-watt light bulb, and subsequently heat treated with ground chrysoberyl at unspecified conditions by a Thai treater. At each stage of the experiments, the samples were photographed and UV-Vis absorption spectra were recorded.
Both the irradiation and Be-diffusion experiments on the iron-doped synthetic corundum created defect centers that had similar UV-Vis absorption curves and produced yellow coloration. The yellow color was unstable when induced by irradiation, but was stable after Be-diffusion.
Experiments on the chromium-doped synthetic corundum produced orange coloration (and similar UV-Vis absorption patterns) by both irradiation and Be-diffusion heating methods. Again, the orange color was unstable when induced by irradiation (and quickly faded to pink), but remained stable after Be-diffusion. These results confirm that divalent Be acts as a stabilizer of defect centers or color centers in iron-doped and chromium-doped synthetic corundum. Hence, the spectrum produced by the irradiation of Fe-doped or Cr-doped synthetic corundum was attributed to metal-related unstable color centers, while that produced in synthetic corundum doped with Be + Fe + or Be + Cr was caused by Be²+ + metal-related stable color centers.
Friday, June 08, 2007
The Hidden Transparency
Chaim Even-Zohar writes about supplier of choice contracts + DTC's problems communicating with the sightholders @ http://www.idexonline.com/portal_FullEditorial.asp
Subjectivity In Gemology
How true! In a way gemology is a magic blend of subjectivity + objectivity + the expert who knows how to connect with the world makes all the difference in a day. Can anyone express the allure, fineness, attraction and glamor in alpha numerical notation? I doubt it.
Ronald Ringsrud (Ronald Ringsrud Co, California) writes:
The analytical mind cannot encapsulate the full experience of viewing a beautiful gem. The detailed objective perceptions of the intellect are supplemented by another style of perception—that of subjective perception. It is holistic and devoid of the mental activity of analysis.
Connoisseurs of gems develop the ability, during a lifetime of viewing fine gems, to go beyond the boundaries of the intellect and witness the glorious aesthetics that a fine gemstone has to offer. From a physiological standpoint, this could be called shifting from brain activity dominated by the left hemisphere (responsible for analysis and discrimination) to that of the right hemisphere (contextual and nonverbal functions).
Gemology’s fullest expression as a discipline is exemplified when both objective and subjective approaches are used. Therefore, physics, optics, and chemistry are taught in gemological institutes alongside history, romance, and folklore. The work of gemologists Dr Edward Gubelin expressed not only objective science but also subjectivity; gemstone certificates from his laboratory had the usual page of objective determinations for the gemstone, but also a page of subjective description outlining the beauty, uniqueness, rarity of the gem.
Dr Gubelin went to encourage work in the use of poetry to describe gemstone aesthetics, which, in an industry sustained by the romancing sale of gemstones, should be recognized as worthy of the highest endeavor.
Fredrick Kunz decried the arbitrary alteration of the birthstone chart by an association of jewelers in 1912. He recognized the multicultural reality that gemstones are special to people born on certain months. Modern understanding of an ancient eastern astrological system sheds new light on this. Practitioners of traditional Asian medicine prescribed gems not only as talismans but also as pharmaceuticals.
Gemology is perhaps more suited to address subjectivity than other sciences simply because its focus, gemstones, involves the complete expressions of the highest subjective qualities: allure, fineness, attraction, glamour, and charm. The role of subjectivity in gemology is interdisciplinary and should elevate our expectations of future gemologists and gemstone dealers.
Ronald Ringsrud (Ronald Ringsrud Co, California) writes:
The analytical mind cannot encapsulate the full experience of viewing a beautiful gem. The detailed objective perceptions of the intellect are supplemented by another style of perception—that of subjective perception. It is holistic and devoid of the mental activity of analysis.
Connoisseurs of gems develop the ability, during a lifetime of viewing fine gems, to go beyond the boundaries of the intellect and witness the glorious aesthetics that a fine gemstone has to offer. From a physiological standpoint, this could be called shifting from brain activity dominated by the left hemisphere (responsible for analysis and discrimination) to that of the right hemisphere (contextual and nonverbal functions).
Gemology’s fullest expression as a discipline is exemplified when both objective and subjective approaches are used. Therefore, physics, optics, and chemistry are taught in gemological institutes alongside history, romance, and folklore. The work of gemologists Dr Edward Gubelin expressed not only objective science but also subjectivity; gemstone certificates from his laboratory had the usual page of objective determinations for the gemstone, but also a page of subjective description outlining the beauty, uniqueness, rarity of the gem.
Dr Gubelin went to encourage work in the use of poetry to describe gemstone aesthetics, which, in an industry sustained by the romancing sale of gemstones, should be recognized as worthy of the highest endeavor.
Fredrick Kunz decried the arbitrary alteration of the birthstone chart by an association of jewelers in 1912. He recognized the multicultural reality that gemstones are special to people born on certain months. Modern understanding of an ancient eastern astrological system sheds new light on this. Practitioners of traditional Asian medicine prescribed gems not only as talismans but also as pharmaceuticals.
Gemology is perhaps more suited to address subjectivity than other sciences simply because its focus, gemstones, involves the complete expressions of the highest subjective qualities: allure, fineness, attraction, glamour, and charm. The role of subjectivity in gemology is interdisciplinary and should elevate our expectations of future gemologists and gemstone dealers.
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