Wednesday, June 13, 2007
The End Of 350 Years Of London’s Distribution Hegemony
Chaim Even-Zohar writes about the current developments at Diamond Trading Company + the ancient diamond trade from India to Europe at various times + world's center of rough diamond: London @ http://www.idexonline.com/portal_FullEditorial.asp?TextSearch=&KeyMatch=0&id=27464
Predicting The Elusive Fourth C
Antwerp Facets (April 2007) writes:
A machine that will predict a diamond’s clarity has proven an elusive goal in the industry. Indeed, the difficulty in doing so left clarity as the only one of the 4C’s which could not be forecast by readily available technology.
An Antwerp company set up last year, however, believes it has created equipment that will give diamantaires the ultimate solution to diamond planning, since they will be able to see inclusions and their precise location.
Matrix Diamond Technology was established by Paul Van der Steen and Ziad Al-Ahmadi. Van der Steen, with 30 years of experience in the diamond manufacturing business, is responsible for the firm’s proprietary technology, while Al-Ahmadi, who has long experience in the cutting and manufacturing of stones, provides the hands-on diamond expertise.
Matrix Diamond Technology came about as the result of a relationship with a Russian company called Octanus. It involves a scanner that measures the outside geometry or topography of the diamond, and then enables the diamantaire, in Van der Steen’s words, ‘to look right into the stone and see what is inside. If you have the exact location of inclusions, this allows the full optimization of the rough stone so that the most highly efficient and high-yielding polished diamond can be produced. This is the ultimate dream, because this gives the diamantaire the map of the rough diamond. The only way currently to get a similar view is to polish little windows on the rough stone to look inside it. Our software shows you the best sawing plane, the best place to cut the diamond for optimal results. That’s why our slogan is ‘Ever dreamt of polishing the same stone twice.’
A built-in price list enables real time decisions on the best cuts and sizes by providing up-to-the minute prices. This means that the system can change the user’s original plans for how he planned to cut the stone. It shows how to cut the main stone and what type and size of satellite stones can be achieved. ‘The Matrix vision is that if you cannot get close enough commercially to the value of the diamond then you will not be able to compete in the market. We are bringing substantial added value,’ Van der Steen explained.
The system’s camera takes 800 shadow pictures as the basis for creating a 3-D model of the stone, and 200 images as the diamond is turned which allows the 3-D model to be placed on top of a picture of the rough. This allows the precise location of inclusions to be seen on the photograph of the diamond. ‘With a microscope you are not able to see as precisely where the inclusions are, but with our system you see its exact location,’ Van der Steen explained, adding that inclusions can be identified down to the level of VVS1.
Regarding the issue of increasing yields, he said there were three levels for achieving this, and thus improving margins. ‘The first one is key weights. There are certain situations where a small difference in weight equals a very large difference in price. Take two stones, one weighing 4.95 carats and the other 5.03 carats. That tiny difference in weight is very large in money terms. It is important to increase the key weights. If you have stones weighing 5.5 carats and 4.7 carats, our system finds solutions that allow for creating two stones of 5 carats each.’
Next, there is the problem associated with the classic approach to rough planning where a relatively large reserve is needed when sawing on the cutting plane for the main stone. This usually means the secondary stone is much smaller due to the need for a reserve. And then, after cutting, the reserve on the main stone is polished off which is clearly a waste of the rough. ‘Due to our precise capabilities, we reduce the reserve and save more of the diamond. Diamantaires want to raise their margins and these are classic ways to do so,’ Van den Steen said.
The third level relates to the optimizing of a stone being cut into two or more diamonds. ‘In the classic way, the main stone is cut, and only then one looks at the possibilities for the other stones. This optimization is important because in a 20 carat stone, for example, the satellite stones can be 3 carats each. Here, you can take an overview of the stone and see all the possibilities right from the beginning.’
Meanwhile, Al Ahmadi, the owner of United Cutting and Marketing, said Matrix is projecting itself to strategic partners such as serious rough suppliers. ‘All diamond companies want to add value to their stock. Miners, for example, are looking to add to their margins. I believe they are selling at a lower price than they could achieve if they knew more precisely what was in the diamond.’
He said the end game for Matrix is as a partner to a big brother and supplying them with high-tech equipment that has been unequivocally proven. ‘The system was born out of necessity since margins have become so small nowadays. A system like this would not have been developed 20 years ago because the margins then allowed all diamond firms, from sightholders to small and medium firms to manufacture and get away with healthy margins. Put simply: the business was easier then.’
Al Ahmadi said many diamantaires were barely making any profit. ‘We are offering solutions based on our knowledge of the industry. The miners supply their clients, but they do not know exactly what their clients are getting from the stones. With our system, we can tell them precisely what is in the stone. Sighholders, today more than ever, need results and our system helps them achieve that because we can eliminate mistakes. We are currently talking with two of the top 10 sightholders in the world about using our system. They are giving us diamonds to work on with them as partners.’
A machine that will predict a diamond’s clarity has proven an elusive goal in the industry. Indeed, the difficulty in doing so left clarity as the only one of the 4C’s which could not be forecast by readily available technology.
An Antwerp company set up last year, however, believes it has created equipment that will give diamantaires the ultimate solution to diamond planning, since they will be able to see inclusions and their precise location.
Matrix Diamond Technology was established by Paul Van der Steen and Ziad Al-Ahmadi. Van der Steen, with 30 years of experience in the diamond manufacturing business, is responsible for the firm’s proprietary technology, while Al-Ahmadi, who has long experience in the cutting and manufacturing of stones, provides the hands-on diamond expertise.
Matrix Diamond Technology came about as the result of a relationship with a Russian company called Octanus. It involves a scanner that measures the outside geometry or topography of the diamond, and then enables the diamantaire, in Van der Steen’s words, ‘to look right into the stone and see what is inside. If you have the exact location of inclusions, this allows the full optimization of the rough stone so that the most highly efficient and high-yielding polished diamond can be produced. This is the ultimate dream, because this gives the diamantaire the map of the rough diamond. The only way currently to get a similar view is to polish little windows on the rough stone to look inside it. Our software shows you the best sawing plane, the best place to cut the diamond for optimal results. That’s why our slogan is ‘Ever dreamt of polishing the same stone twice.’
A built-in price list enables real time decisions on the best cuts and sizes by providing up-to-the minute prices. This means that the system can change the user’s original plans for how he planned to cut the stone. It shows how to cut the main stone and what type and size of satellite stones can be achieved. ‘The Matrix vision is that if you cannot get close enough commercially to the value of the diamond then you will not be able to compete in the market. We are bringing substantial added value,’ Van der Steen explained.
The system’s camera takes 800 shadow pictures as the basis for creating a 3-D model of the stone, and 200 images as the diamond is turned which allows the 3-D model to be placed on top of a picture of the rough. This allows the precise location of inclusions to be seen on the photograph of the diamond. ‘With a microscope you are not able to see as precisely where the inclusions are, but with our system you see its exact location,’ Van der Steen explained, adding that inclusions can be identified down to the level of VVS1.
Regarding the issue of increasing yields, he said there were three levels for achieving this, and thus improving margins. ‘The first one is key weights. There are certain situations where a small difference in weight equals a very large difference in price. Take two stones, one weighing 4.95 carats and the other 5.03 carats. That tiny difference in weight is very large in money terms. It is important to increase the key weights. If you have stones weighing 5.5 carats and 4.7 carats, our system finds solutions that allow for creating two stones of 5 carats each.’
Next, there is the problem associated with the classic approach to rough planning where a relatively large reserve is needed when sawing on the cutting plane for the main stone. This usually means the secondary stone is much smaller due to the need for a reserve. And then, after cutting, the reserve on the main stone is polished off which is clearly a waste of the rough. ‘Due to our precise capabilities, we reduce the reserve and save more of the diamond. Diamantaires want to raise their margins and these are classic ways to do so,’ Van den Steen said.
The third level relates to the optimizing of a stone being cut into two or more diamonds. ‘In the classic way, the main stone is cut, and only then one looks at the possibilities for the other stones. This optimization is important because in a 20 carat stone, for example, the satellite stones can be 3 carats each. Here, you can take an overview of the stone and see all the possibilities right from the beginning.’
Meanwhile, Al Ahmadi, the owner of United Cutting and Marketing, said Matrix is projecting itself to strategic partners such as serious rough suppliers. ‘All diamond companies want to add value to their stock. Miners, for example, are looking to add to their margins. I believe they are selling at a lower price than they could achieve if they knew more precisely what was in the diamond.’
He said the end game for Matrix is as a partner to a big brother and supplying them with high-tech equipment that has been unequivocally proven. ‘The system was born out of necessity since margins have become so small nowadays. A system like this would not have been developed 20 years ago because the margins then allowed all diamond firms, from sightholders to small and medium firms to manufacture and get away with healthy margins. Put simply: the business was easier then.’
Al Ahmadi said many diamantaires were barely making any profit. ‘We are offering solutions based on our knowledge of the industry. The miners supply their clients, but they do not know exactly what their clients are getting from the stones. With our system, we can tell them precisely what is in the stone. Sighholders, today more than ever, need results and our system helps them achieve that because we can eliminate mistakes. We are currently talking with two of the top 10 sightholders in the world about using our system. They are giving us diamonds to work on with them as partners.’
Tuesday, June 12, 2007
New Diamond Newsletter
(via JCK) Diamond Finance describes itself as the only newsletter dedicated to finance and accounting in the diamond and jewelry industry. It includes an interview with HSBC's Jeff Pfeffer. Check out the first issue here (PDF).
The Keshi Pearl Issue
Nick Sturman (Directorate of Precious Metals and Gemstone Testing, Ministry of Industry and Commerce, Bahrain) writes:
The word Keshi has traditionally been used to describe small natural saltwater pearls (seed pearls) as well as similarly sized pearls that resulted as a byproduct of the Japanese cultured pearl industry. Nowadays, the term is predominantly used to describe cultured pearls with sizes well above those that would be considered seed-like. Hence, Keshi is now used generically to describe any pearl byproduct without a bead nucleus that is produced by the culturing process regardless of the ocean in which the pearl farm is located.
The contentious aspect of Keshi cultured pearls revolved around the following questions: Can gemological laboratories differentiate between all Keshi cultured pearls and natural pearls? In our opinion and experience, the answer to this question is no. Some Keshi cultured pearls are instantly recognizable by their overall visual appearance, and their cultured origin can be further validated by their internal structural features, as revealed by X-radiography. In other cases, laboratories are faced with an identification issue that may either straightforward (i.e., the X-radiographic structures are quite distinct, classifying them as tissue-nucleated cultured pearls) or difficult (i.e., they exhibit natural-appearing structures).
Quantity testing of Keshi cultured pearls (i.e., in rows, necklaces, or parcels) may be thought of as less complicated because the test results are based on those samples that show the most evident structures. However, this is not always true, and we often have to issue mixture, majority/minority, or even natural reports on parcels of what appear to be Keshi cultured pearls. When individual pearls are submitted (i.e., for a full test as opposed to batch testing), the situation may be trickier since only the structure of a single sample, and not a group of pearls, is available to the gemologist. If the structure appears natural by X-radiography, then a natural report can be issued. In our experience, individual pearls with internal structures that are undoubtedly natural will pass as such in most, if not all, laboratories.
We do not have a solution to the differences in opinion that exist in the trade regarding what constitutes a Keshi pearl, and believe that a good deal of research still needs to be carried out on the subject.
The word Keshi has traditionally been used to describe small natural saltwater pearls (seed pearls) as well as similarly sized pearls that resulted as a byproduct of the Japanese cultured pearl industry. Nowadays, the term is predominantly used to describe cultured pearls with sizes well above those that would be considered seed-like. Hence, Keshi is now used generically to describe any pearl byproduct without a bead nucleus that is produced by the culturing process regardless of the ocean in which the pearl farm is located.
The contentious aspect of Keshi cultured pearls revolved around the following questions: Can gemological laboratories differentiate between all Keshi cultured pearls and natural pearls? In our opinion and experience, the answer to this question is no. Some Keshi cultured pearls are instantly recognizable by their overall visual appearance, and their cultured origin can be further validated by their internal structural features, as revealed by X-radiography. In other cases, laboratories are faced with an identification issue that may either straightforward (i.e., the X-radiographic structures are quite distinct, classifying them as tissue-nucleated cultured pearls) or difficult (i.e., they exhibit natural-appearing structures).
Quantity testing of Keshi cultured pearls (i.e., in rows, necklaces, or parcels) may be thought of as less complicated because the test results are based on those samples that show the most evident structures. However, this is not always true, and we often have to issue mixture, majority/minority, or even natural reports on parcels of what appear to be Keshi cultured pearls. When individual pearls are submitted (i.e., for a full test as opposed to batch testing), the situation may be trickier since only the structure of a single sample, and not a group of pearls, is available to the gemologist. If the structure appears natural by X-radiography, then a natural report can be issued. In our experience, individual pearls with internal structures that are undoubtedly natural will pass as such in most, if not all, laboratories.
We do not have a solution to the differences in opinion that exist in the trade regarding what constitutes a Keshi pearl, and believe that a good deal of research still needs to be carried out on the subject.
Emerald Crack-Up
Gary Roskin writes about a new development in the field of emerald enhancement that could mean trouble for retail jewelers @ http://www.jckonline.com/article/CA6447698.html
Tomorrow’s Dirty Diamonds
Chaim Even-Zohar writes about Alan Bond, the flamboyant entrepreneur and his contacts in southern Lebanon @ http://www.idexonline.com/portal_FullEditorial.asp?TextSearch=&KeyMatch=0&id=27430
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.
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