By Richard Falkiner
Barrie & Rockliff
The Cresset Press
1968
The Cresset Press writes:
Until comparatively recently, many pieces of antique jewellery could be bought for token prices. Sadly, this is no longer true today. As with so many other types of antiques, the price of jewellery has risen dramatically, above all over the past decade. The basic reason for this is, of course, that in an era when traditional forms of currency have proved so vulnerable to economic depressions, first class antiques, acquired with care and knowledge have shown themselves to be outstanding investments.
In spite of the recent rise in prices, there is still a large amount of antique jewellery available to the intelligent collector with even a modest budget. Much of this jewellery was virtually ignored for many years and has only recently begun to be appreciated. For instance, paste jewellery was long regarded as of value almost exclusively for the melt down prices commanded by its silver mounts. Today, a fine piece of past is recognized for what it is—an object of intrinsic decorative worth which, nonetheless, can be acquired for a fraction of the price fetched by a comparable object set with gems.
While there have been several works on antique jewellery (although most of them are now out of print), this book deals for the first time with the subject as an investment. Mr Falkiner’s approach is chronological, providing a chapter by chapter outline of the history of jewellery from the very earliest times, and illustrating each chapter with a wide range of photographs of over 200 objects. Many of the pieces illustrated have absorbing historical connotations: the Alfred jewel, lost by Alfred the Great at the end of the 9th century when he was a fugitive in Athelney Marsh and not found again until the 17th century; a jewel found in the baggage of the ill-fated Charles I after the battle of Naseby; the memorial rings of Beau Brummel and George Washington. The detailed captions to the pictures comment on prices fetched in the past and indicate possible trends for the future.
In addition, there is a substantial technological section in which Mr Falkiner traces the etymology of many of the terms used in jewellery, and explains in layman’s language the concepts of the refractive index, specific gravity, the cutting of stones, etc. With its 16 pages of magnificent color plates, this superbly produced volume, directed primarily at the investor-collector, will be a welcome addition to the New Currency Series.
P.J.Joseph's Weblog On Colored Stones, Diamonds, Gem Identification, Synthetics, Treatments, Imitations, Pearls, Organic Gems, Gem And Jewelry Enterprises, Gem Markets, Watches, Gem History, Books, Comics, Cryptocurrency, Designs, Films, Flowers, Wine, Tea, Coffee, Chocolate, Graphic Novels, New Business Models, Technology, Artificial Intelligence, Robotics, Energy, Education, Environment, Music, Art, Commodities, Travel, Photography, Antiques, Random Thoughts, and Things He Like.
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Thursday, January 25, 2007
Wednesday, January 24, 2007
Business Management
Warren Edward Buffett, CEO, Berkshire Hathaway writes:
'When a management with a reputation for brilliance tackles a business with a poor reputation for fundamental economics, it is the reputation of the business that stays intact.'
'When a management with a reputation for brilliance tackles a business with a poor reputation for fundamental economics, it is the reputation of the business that stays intact.'
The Federal Trade Commission’s Guide for the Jewelry, Precious Metals and Pewter Industries
FTC writes:
23.0 Scope and application
(a) These guides apply to jewelry industry products, which include, but are not limited to, the following: gemstones and their laboratory-created and imitation substitutes; natural and cultured pearls and their imitations; and metallic watch bands not permanently attached to watches.1 These guides also apply to articles, including optical frames, pens and pencils, flatware, and hollowware, fabricated from precious metals (gold, silver and platinum group metals), precious metal alloys, and their imitations. These guides also apply to all articles made from pewter. For the purposes of these guides, all articles covered by these guides are defined as "industry products."
(b) These guides apply to persons, partnerships, or corporations, at every level of the trade (including but not limited to manufacturers, suppliers, and retailers) engaged in the business of offering for sale, selling, or distributing industry products.
Note to paragraph (b): To prevent consumer deception, persons, partnerships, or corporations in the business of appraising, identifying, or grading industry products should utilize the terminology and standards set forth in the guides.
(c) These guides apply to claims and representations about industry products included in labeling, advertising, promotional materials, and all other forms of marketing, whether asserted directly or by implication, through words, symbols, emblems, logos, illustrations, depictions, product brand names, or through any other means.
More info @ http://www.ftc.gov/bcp/guides/jewel-gd.htm
23.0 Scope and application
(a) These guides apply to jewelry industry products, which include, but are not limited to, the following: gemstones and their laboratory-created and imitation substitutes; natural and cultured pearls and their imitations; and metallic watch bands not permanently attached to watches.1 These guides also apply to articles, including optical frames, pens and pencils, flatware, and hollowware, fabricated from precious metals (gold, silver and platinum group metals), precious metal alloys, and their imitations. These guides also apply to all articles made from pewter. For the purposes of these guides, all articles covered by these guides are defined as "industry products."
(b) These guides apply to persons, partnerships, or corporations, at every level of the trade (including but not limited to manufacturers, suppliers, and retailers) engaged in the business of offering for sale, selling, or distributing industry products.
Note to paragraph (b): To prevent consumer deception, persons, partnerships, or corporations in the business of appraising, identifying, or grading industry products should utilize the terminology and standards set forth in the guides.
(c) These guides apply to claims and representations about industry products included in labeling, advertising, promotional materials, and all other forms of marketing, whether asserted directly or by implication, through words, symbols, emblems, logos, illustrations, depictions, product brand names, or through any other means.
More info @ http://www.ftc.gov/bcp/guides/jewel-gd.htm
Q & A: Conflict Diamonds
Guardian Unlimited writes:
All you need to know about the industry's efforts to shake off the blood-soaked image of stones extracted from the world's war zones.
Where do conflict diamonds come from?
These are stones extracted from rebel-held areas or in defiance of security council resolutions, and used to pay for weapons. The end of several African civil wars has left Ivory Coast as the world's prime source of conflict diamonds. A recent UN report found that rough diamonds were being smuggled out of the rebel-held north and certified for the international market by dealers in Ghana and Mali. The UN experts said that up to US$23m-worth was being smuggled out annually in a trade controlled by the rebel New Forces. Campaigners say this shows there are still crucial gaps in the diamond certification scheme known as the Kimberley process. "These are conflict diamonds, and some of them have gone to Ghana where they're stamped as conflict-free," said Nick Dearden, campaigns manager of Amnesty International.
Congo is another troublespot. Last month, the World Diamond Council, the industry body, said it had received reports of conflict diamonds being smuggled from Congo via Zimbabwe to South Africa where they were certified as legitimate and exported. Zimbabwe's government denies the allegations. Although Liberia's civil war is over, its diamonds are still subject to UN sanctions.
What is the scale of the problem?
Conflict diamonds, chiefly from Congo, Angola and Sierra Leone, made up between 4% and 15% of the global trade when those countries' wars were at their height in the late 1990s. The industry says that fewer than 1% of diamonds on the market now are from war zones. Gemstone revenue has the potential to heal as well as hurt, the industry says, pointing out that Sierra Leone has now been at peace since 2002 and its diamond industry generates $140m in tax and export revenue. But critics say 1% of a $60bn global market is still too much.
A total of 69 countries have now signed up to the Kimberley process, which was meant to stop diamonds being used to fund conflict. Governments have to keep records tracking diamonds from source to their polished form. In theory, this prevents conflict diamonds from entering the supply chain.
Is it ethical to buy diamonds?
Despite bad publicity, a big rock remains synonymous with romance. Retail diamond sales totalled £1.2bn in the UK in 2005, according to industry figures, and sales are rising. One US jeweller has sought to bypass human rights concerns by selling only Canadian diamonds. But both the industry and campaigners say this could hurt some of the world's poorest people.
In countries such as Botswana and South Africa, diamond revenues have paid for schools, roads and clinics. Instead of boycotting diamonds altogether, consumers are being urged to ask retailers whether their diamonds are conflict-free. Alex Yearsley of Global Witness, whose campaigns focus on the corrupt exploitation of natural resources, said: "Consumers have the power to effect industry-wide changes simply by demanding that their diamonds are clean."
More info @
http://www.guardian.co.uk/international/story/0,,1996072,00.html
All you need to know about the industry's efforts to shake off the blood-soaked image of stones extracted from the world's war zones.
Where do conflict diamonds come from?
These are stones extracted from rebel-held areas or in defiance of security council resolutions, and used to pay for weapons. The end of several African civil wars has left Ivory Coast as the world's prime source of conflict diamonds. A recent UN report found that rough diamonds were being smuggled out of the rebel-held north and certified for the international market by dealers in Ghana and Mali. The UN experts said that up to US$23m-worth was being smuggled out annually in a trade controlled by the rebel New Forces. Campaigners say this shows there are still crucial gaps in the diamond certification scheme known as the Kimberley process. "These are conflict diamonds, and some of them have gone to Ghana where they're stamped as conflict-free," said Nick Dearden, campaigns manager of Amnesty International.
Congo is another troublespot. Last month, the World Diamond Council, the industry body, said it had received reports of conflict diamonds being smuggled from Congo via Zimbabwe to South Africa where they were certified as legitimate and exported. Zimbabwe's government denies the allegations. Although Liberia's civil war is over, its diamonds are still subject to UN sanctions.
What is the scale of the problem?
Conflict diamonds, chiefly from Congo, Angola and Sierra Leone, made up between 4% and 15% of the global trade when those countries' wars were at their height in the late 1990s. The industry says that fewer than 1% of diamonds on the market now are from war zones. Gemstone revenue has the potential to heal as well as hurt, the industry says, pointing out that Sierra Leone has now been at peace since 2002 and its diamond industry generates $140m in tax and export revenue. But critics say 1% of a $60bn global market is still too much.
A total of 69 countries have now signed up to the Kimberley process, which was meant to stop diamonds being used to fund conflict. Governments have to keep records tracking diamonds from source to their polished form. In theory, this prevents conflict diamonds from entering the supply chain.
Is it ethical to buy diamonds?
Despite bad publicity, a big rock remains synonymous with romance. Retail diamond sales totalled £1.2bn in the UK in 2005, according to industry figures, and sales are rising. One US jeweller has sought to bypass human rights concerns by selling only Canadian diamonds. But both the industry and campaigners say this could hurt some of the world's poorest people.
In countries such as Botswana and South Africa, diamond revenues have paid for schools, roads and clinics. Instead of boycotting diamonds altogether, consumers are being urged to ask retailers whether their diamonds are conflict-free. Alex Yearsley of Global Witness, whose campaigns focus on the corrupt exploitation of natural resources, said: "Consumers have the power to effect industry-wide changes simply by demanding that their diamonds are clean."
More info @
http://www.guardian.co.uk/international/story/0,,1996072,00.html
Gemstones with asterism (stars)
Epiasterism = use reflected light
Diasterism = use transmitted light
Most frequently seen star gemstones
- Almandine garnet (4 / 6 / 12 rays: epiasterism / diasterism)
- Beryl (6 rays: epiasterism)
- Corundum (6 / 12 rays: epiasterism)
- Diopside (4 rays (epiasterism)
- Enstatite (4 / 8 rays: epiasterism)
- Moonstone (4 rays: epiasterism)
- Quartz (4 / 6 / 12 or more: diasterism / epiasterism)
Synthetic and imitation star stones
- Corundum doublet / triplet (6 rays: epiasterism)
- Synthetic corundum (6 rays: epiasterism)
- Inscribed base star (any: epiasterism)
- Opal triplet star (6 rays: epiasterism)
- Mirror-backed quartz (4 / 6 / 12 or more: epiasterism)
- Synthetic rutile (4 ray: epiasterism)
Diasterism = use transmitted light
Most frequently seen star gemstones
- Almandine garnet (4 / 6 / 12 rays: epiasterism / diasterism)
- Beryl (6 rays: epiasterism)
- Corundum (6 / 12 rays: epiasterism)
- Diopside (4 rays (epiasterism)
- Enstatite (4 / 8 rays: epiasterism)
- Moonstone (4 rays: epiasterism)
- Quartz (4 / 6 / 12 or more: diasterism / epiasterism)
Synthetic and imitation star stones
- Corundum doublet / triplet (6 rays: epiasterism)
- Synthetic corundum (6 rays: epiasterism)
- Inscribed base star (any: epiasterism)
- Opal triplet star (6 rays: epiasterism)
- Mirror-backed quartz (4 / 6 / 12 or more: epiasterism)
- Synthetic rutile (4 ray: epiasterism)
Emerald and Other Beryls
By John Sinkankas
Chilton Book Company, Radnor, Pennsylvania, USA
1981 ISBN 0-8019-7114-4
Chilton Book Company writes:
This consummate portrait of Emerald and Other Beryls is a permanent reference for jewelers, gemological historians, mineralogists, geologists, and mineral collectors. John Sinkankas, a widely respected authority on the earth sciences, here provides a scholarly yet eminently readable monograph on every facet of beryl: cultural and natural history; structure and composition; lapidary and synthesis; and world occurrences, including gems, collector’s specimens, and the ore of the rare metal beryllium.
Beginning with Egypt 5500 years ago, the author traces the story of the dazzling emerald—from the fabled Table of Solomon to Queen Elizabeth II’s Coronation jewels—and its less renowned relatives, the pink morganite, the golden beryl and the blue aquamarine. The role of beryl in ornament, magic and medicine is a fascinating tale interwoven with history’s most compelling people and events. Together with a unique nomenclature appendix of synonyms in all languages for beryl and its varieties, this cultural archive is of special interest to historians, archeologists, linguists and students of curios lore.
In the second part, Sinkankas explores the natural history of emerald and beryl and the advances in mineralogical knowledge from antiquity, through the Christian Era, the Middle Ages, and into the highly technological modern era of exotic used for a mineral that was once considered suitable only for ornamentation. The author culled and synthesized the extensive literature of every language to bring to one volume all the significant material on crystal structure, chemical composition, physical and optical properties, and causes of color. A chapter is also devoted to cutting emerald and other beryls into jewelry stones.
Unmatched anywhere in the literature, the third part is an encyclopedic guide to major beryl deposits, with special notes on sources of fine crystal specimens and gem materials. Sinkankas has compressed a colossal amount of information into a readily accessible reference for mineralogists, geologists, mineral collectors, and gem cutters. Superbly rendered maps by the author augment the locality data.
In addition to photographs in color and black and white, the text is enhanced by line drawings and a series of unique watercolor paintings of actual crystal specimens done expressly for this book by the author.
About the Author
John Sinkankas has published eleven books on mineralogy, gemology, prospecting, and lapidary art, among them the critically acclaimed Gemstones of North America in two volumes and the popular Mineralogy for Amateurs. He has written more than 100 articles for popular and scientific journals, contributing regularly to Gems and Gemology, Journal of Gemmology, Rocks and Minerals, Gems and Minerals, Lapidary Journal and American Mineralogist.
Chilton Book Company, Radnor, Pennsylvania, USA
1981 ISBN 0-8019-7114-4
Chilton Book Company writes:
This consummate portrait of Emerald and Other Beryls is a permanent reference for jewelers, gemological historians, mineralogists, geologists, and mineral collectors. John Sinkankas, a widely respected authority on the earth sciences, here provides a scholarly yet eminently readable monograph on every facet of beryl: cultural and natural history; structure and composition; lapidary and synthesis; and world occurrences, including gems, collector’s specimens, and the ore of the rare metal beryllium.
Beginning with Egypt 5500 years ago, the author traces the story of the dazzling emerald—from the fabled Table of Solomon to Queen Elizabeth II’s Coronation jewels—and its less renowned relatives, the pink morganite, the golden beryl and the blue aquamarine. The role of beryl in ornament, magic and medicine is a fascinating tale interwoven with history’s most compelling people and events. Together with a unique nomenclature appendix of synonyms in all languages for beryl and its varieties, this cultural archive is of special interest to historians, archeologists, linguists and students of curios lore.
In the second part, Sinkankas explores the natural history of emerald and beryl and the advances in mineralogical knowledge from antiquity, through the Christian Era, the Middle Ages, and into the highly technological modern era of exotic used for a mineral that was once considered suitable only for ornamentation. The author culled and synthesized the extensive literature of every language to bring to one volume all the significant material on crystal structure, chemical composition, physical and optical properties, and causes of color. A chapter is also devoted to cutting emerald and other beryls into jewelry stones.
Unmatched anywhere in the literature, the third part is an encyclopedic guide to major beryl deposits, with special notes on sources of fine crystal specimens and gem materials. Sinkankas has compressed a colossal amount of information into a readily accessible reference for mineralogists, geologists, mineral collectors, and gem cutters. Superbly rendered maps by the author augment the locality data.
In addition to photographs in color and black and white, the text is enhanced by line drawings and a series of unique watercolor paintings of actual crystal specimens done expressly for this book by the author.
About the Author
John Sinkankas has published eleven books on mineralogy, gemology, prospecting, and lapidary art, among them the critically acclaimed Gemstones of North America in two volumes and the popular Mineralogy for Amateurs. He has written more than 100 articles for popular and scientific journals, contributing regularly to Gems and Gemology, Journal of Gemmology, Rocks and Minerals, Gems and Minerals, Lapidary Journal and American Mineralogist.
Tuesday, January 23, 2007
Patience and Discipline
Forbes writes:
Mary Buffett spoke to Forbes.com about patience, discipline and Warren Buffett's pleasure dome.
Forbes.com: What's the most important lesson you've learned from Warren Buffett?
Mary Buffett: Patience and discipline. And doing something you love. So many people -- and Warren has said this -- are doing it for the money. That's really not the right reason. If you're doing something you love, you're more likely to put your all into it, and that generally equates to making money. He always says when he gets up in the morning he goes to his pleasure dome, which is his office.
Mary Buffett spoke to Forbes.com about patience, discipline and Warren Buffett's pleasure dome.
Forbes.com: What's the most important lesson you've learned from Warren Buffett?
Mary Buffett: Patience and discipline. And doing something you love. So many people -- and Warren has said this -- are doing it for the money. That's really not the right reason. If you're doing something you love, you're more likely to put your all into it, and that generally equates to making money. He always says when he gets up in the morning he goes to his pleasure dome, which is his office.
Precious Stones
By Dr Max Bauer
Translated from the German by L.J.Spencer
Charles E Tuttle Company
1969 ISBN 8048-0489-3
Charles E Tuttle Company writes:
A popular account of their characters, occurrence, and application, with an introduction to their determination for mineralogists, lapidaries, and jewelers with an appendix on pearls and coral from the original edition and up-to-date material on synthetic gems and the cultured pearl.
Originally published in 1896 in Germany, Precious Stones was translated and brought up to date in 1903 prior to its publication in England. It is without doubt one of the most comprehensive studies of gems ever published.
Long out of print, Precious Stones appeared high on the list of a response made by antiquarian book dealers who were asked which books they would most like to see reprinted. Although the technology applicable to gems has made enormous strides in this century, the basic information contained in Precious Stones remain valid.
Part One is devoted to a consideration of the mineral characteristics which are of importance to the specialist in gems; a general consideration of the type of occurrence of precious stones; and material relating to the application and working of these stones.
Part Two contains a detailed account of every mineral which has been used for ornamental purposes, with special reference to precious stones.
Part Three epitomizes the characters to be relied on in determining precious stones and distinguishing them from other precious stones and from imitations.
Up-to-date information on synthetic gems and the cultured pearl is included in the appendices to the new edition.
Precious Stones deserves a place in the reference library of all professional people who are concerned with gems and mineralogy.
Translated from the German by L.J.Spencer
Charles E Tuttle Company
1969 ISBN 8048-0489-3
Charles E Tuttle Company writes:
A popular account of their characters, occurrence, and application, with an introduction to their determination for mineralogists, lapidaries, and jewelers with an appendix on pearls and coral from the original edition and up-to-date material on synthetic gems and the cultured pearl.
Originally published in 1896 in Germany, Precious Stones was translated and brought up to date in 1903 prior to its publication in England. It is without doubt one of the most comprehensive studies of gems ever published.
Long out of print, Precious Stones appeared high on the list of a response made by antiquarian book dealers who were asked which books they would most like to see reprinted. Although the technology applicable to gems has made enormous strides in this century, the basic information contained in Precious Stones remain valid.
Part One is devoted to a consideration of the mineral characteristics which are of importance to the specialist in gems; a general consideration of the type of occurrence of precious stones; and material relating to the application and working of these stones.
Part Two contains a detailed account of every mineral which has been used for ornamental purposes, with special reference to precious stones.
Part Three epitomizes the characters to be relied on in determining precious stones and distinguishing them from other precious stones and from imitations.
Up-to-date information on synthetic gems and the cultured pearl is included in the appendices to the new edition.
Precious Stones deserves a place in the reference library of all professional people who are concerned with gems and mineralogy.
Chatoyant (Cat’s eye) gemstones
Most frequently seen cat’s eye gemstones
- Actinolite
- Apatite
- Beryl
- Chrysoberyl
- Diopside
- Gypsum
- Moonstone
- Quartz’s cat’s eye
- Tiger’s Eye (trade name) Quartz
- Tourmaline
Most frequently seen imitation cat’s eyes gemstones
- Cathaystone (fiberoptic glass)
- Glass
- Ulexite-base doublet
- Victoria cat’s eye (devitrified glass)
- Fire eye (chatoyant glass)
- Actinolite
- Apatite
- Beryl
- Chrysoberyl
- Diopside
- Gypsum
- Moonstone
- Quartz’s cat’s eye
- Tiger’s Eye (trade name) Quartz
- Tourmaline
Most frequently seen imitation cat’s eyes gemstones
- Cathaystone (fiberoptic glass)
- Glass
- Ulexite-base doublet
- Victoria cat’s eye (devitrified glass)
- Fire eye (chatoyant glass)
How To Separate Frequently Encountered Yellow Stones
- Visual observation: (10x lens) Look for color, luster, cut, doublet/triplet junctions, if any.
- Determine optic character: Single refractive (SR) / Double refractive (DR) / Anomalous Double refractive (ADR) / Aggregate (AGG).
- Spectrum: Many yellow stones may have diagnostic spectrum.
- Microscope: Inclusions may be diagnostic, but look for inclusions that differentiate natural and synthetic, doublet / triplet.
- Dichroscope: Different cutting orientations of natural and synthetic corundum may be revealed by dichroscope.
- Fluorescence: Look under shortwave and longwave for diagnostic colors.
- Immersion cell: Use immersion cell and high refractive index liquid to separate doublets/triplets.
- Refractometer: Confirm spectroscope reading with refractometer.
The yellow stones, which may resemble one another in appearance and values, are:
Quartz, Citrine
- Hardness: 7
- Specific gravity: 2.65
- Refractive index: 1.54 – 1.55
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.009
- Other points: Color, inclusions. Citrine may be treated. Gem quality stones are relatively clean. Common look-alikes are yellow beryl, yellow labradorite, scapolite, and glass. Standard / analytical techniques may be required to detect treatments / identify stones.
Synthetic quartz , citrine
- Hardness: 7
- Specific gravity: 2.65
- Refractive index: 1.54 – 1.55
- Optic sign: Uniaxial positive
- Birefringence: DR; 0.009
- Other points: Color, inclusions, twinning pattern. Synthetic citrine is produced by the hydrothermal process. Gem quality stones are relatively clean. Standard / analytical techniques may be required to identify stones.
Feldspar, Orthoclase
- Hardness: 6
- Specific gravity: 2.56
- Refractive index: 1.52 – 1.53
- Optic sign: Biaxial negative
- Birefringence: DR; 0.006
- Other points: Color, inclusions, cleavage. Gem quality stones are relatively clean. Common look-alikes are yellow beryl, citrine, scapolite, and glass. Standard / analytical techniques may be required to identify stones.
Feldspar, Labradorite
- Hardness: 6
- Specific gravity: 2.70 (average)
- Refractive index: 1.56 – 1.57
- Optic sign: Biaxial positive
- Birefringence: DR; 0.009
- Other points: Color, inclusions, cleavage. Gem quality stones are relatively clean. Common look-alikes are yellow beryl, citrine, scapolite, and glass. Standard / analytical techniques may be required to identify stones.
Beryl
- Hardness: 7.75
- Specific gravity: 2.70 – 2.90
- Refractive index: 1.56 – 1.59
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.005/9
- Other points: Color, inclusions. Gem quality stones are relatively clean. Yellow beryl may treated. Common look-alikes are yellow labradorite, citrine, scapolite, and glass. Standard / analytical techniques may be required to identify stones.
Scapolite
- Hardness: 6
- Specific gravity: 2.50-2.70
- Refractive index: 1.54 – 1.58
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.009 - 026
- Other points: Color, inclusions, fluorescence. Gem quality stones are relatively clean. Common look-alikes are yellow labradorite, citrine, yellow beryl, and glass. Standard / analytical techniques may be required to identify stones.
Apatite
- Hardness: 5
- Specific gravity: 3.18
- Refractive index: 1.63 – 1.64
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.002 – 0.004
- Other points: Color, inclusions, spectrum. Apatite may be treated. Gem quality stones are relatively clean. Common imitations include chrysoberyl, sapphire, tourmaline, danburite, peridot, topaz and glass. Standard / analytical techniques may be required to identify stones.
Danburite
- Hardness: 7
- Specific gravity: 3.00
- Refractive index: 1.63 – 1.64
- Optic sign: Biaxial negative
- Birefringence: DR; 0.006
- Other points: Color, inclusions, spectrum. Gem quality stones are relatively clean. Common imitations include chrysoberyl, sapphire, tourmaline, apatite, peridot, topaz and glass. Standard / analytical techniques may be required to identify stones.
Topaz
- Hardness: 8
- Specific gravity: 3.53
- Refractive index: 1.63 – 1.64
- Optic sign: Biaxial positive
- Birefringence: DR; 0.008
- Other points: Color, inclusions, cleavage. Topaz may be treated. Gem quality stones are relatively clean. Common imitations include chrysoberyl, sapphire, tourmaline, apatite, peridot, danburite and glass. Standard / analytical techniques may be required to detect treatments / identify stones.
Tourmaline
- Hardness: 7
- Specific gravity: 3.05
- Refractive index: 1.62 – 1.64
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.018
- Other points: Color, inclusions, doubling of back facets, pleochroism. Tourmaline may be treated. Gem quality stones are relatively clean. Common imitations include chrysoberyl, sapphire, topaz, apatite, peridot, danburite and glass. Standard / analytical techniques may be required to detect treatments / identify stones.
Idocrase
- Hardness: 6.5
- Specific gravity: 3.35
- Refractive index: 1.70 – 1.73
- Optic sign: Uniaxial negative / positive
- Birefringence: DR; 0.005
- Other points: Color, spectrum. Common imitations include chrysoberyl, sapphire, topaz, apatite, peridot, danburite, tourmaline, and glass. Standard / analytical techniques may be required to detect treatments / identify stones.
Grossular garnet
- Hardness: 7.25
- Specific gravity: 3.60 – 3.70
- Refractive index: 1.74 – 1.75
- Optic sign: SR
- Birefringence: -
- Other points: Color, inclusions. Gem quality stones are relatively clean. Common imitations include chrysoberyl, sapphire, topaz, apatite, peridot, danburite, tourmaline, and glass. Standard / analytical techniques may be required to detect treatments / identify stones.
Chrysoberyl
- Hardness: 8.5
- Specific gravity: 3.72
- Refractive index: 1.74 – 1.75
- Optic sign: Biaxial positive
- Birefringence: DR; 0.009
- Other points: Color, inclusions, spectrum. Chrysoberyl may be treated. Gem quality stones are relatively clean. Common imitations include idocrase, hessonite garnet, sapphire, topaz, apatite, peridot, danburite, tourmaline, and glass. Standard / analytical techniques may be required to detect treatments / identify stones.
Sapphire
- Hardness: 9
- Specific gravity: 4
- Refractive index: 1.76 – 1.77
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.008
- Other points: Color, inclusions, spectrum. Yellow sapphire may be treated. Gem quality stones are relatively clean. Common imitations include chrysoberyl, idocrase, hessonite garnet, topaz, apatite, peridot, danburite, tourmaline, and glass. Standard / analytical techniques may be required to detect treatments / identify stones.
Andradite garnet (yellow demantoid)
- Hardness: 6.5
- Specific gravity: 3.85
- Refractive index: 1.89
- Optic sign: SR
- Birefringence: -
- Other points: Color, inclusions, negative refractive index reading, spectrum, dispersion, luster. Common imitations include chrysoberyl, idocrase, sapphire, topaz, apatite, peridot, danburite, tourmaline, zircon, sphene, and glass. Standard / analytical techniques may be required to detect treatments / identify stones.
Zircon
- Hardness: 7.5
- Specific gravity: 4.69
- Refractive index: 1.93 – 1.99
- Optic sign: Uniaxial positive
- Birefringence: DR; 0.059
- Other points: Color, inclusions, doubling of back facets, spectrum, luster. Zircon may be treated. Gem quality stones are relatively clean. Common imitations include chrysoberyl, idocrase, sapphire, topaz, apatite, peridot, danburite, tourmaline, demantoid garnet, sphene and glass. Standard / analytical techniques may be required to detect treatments / identify stones.
Sphene
- Hardness: 5.5
- Specific gravity: 3.53
- Refractive index: 1.89 – 2.02
- Optic sign: Biaxial positive
- Birefringence: DR; 0.051
- Other points: Color, negative refractive index reading, dispersion, doubling of back facets, spectrum. Common imitations include chrysoberyl, idocrase, sapphire, topaz, apatite, peridot, danburite, tourmaline, zircon, demantoid garnet and glass. Standard / analytical techniques may be required to detect treatments / identify stones.
Synthetic cubic zirconia
- Hardness: 8.5
- Specific gravity: 5.65+
- Refractive index: 2.15+
- Optic sign: SR
- Birefringence: -
- Other points: Color, inclusions, negative refractive index, luster, dispersion, orange flash on the pavilion. Most gem quality stones are relatively clean. High dispersion will easily identify the stone. Standard / analytical techniques may be required to identify stones.
Diamond
- Hardness: 10
- Specific gravity: 3.52
- Refractive index: 2.42
- Optic sign: SR/ADR
- Birefringence: -
- Other points: Color, negative refractive index reading, dispersion, spectrum, inclusions. Yellow diamonds may be treated. Gem quality stones are relatively clean. Common imitations are synthetic cubic zirconia, synthetic moissanite, synthetic strontium titanate, GGG and glass. Analytical / standard techniques may be required to detect treatments / identify the stones.
Synthetic diamond
- Hardness: 10
- Specific gravity: 3.52
- Refractive index: 2.42
- Optic sign: SR/ADR
- Birefringence: -
- Other points: Color, negative refractive index reading, dispersion, spectrum, inclusions. Synthetic yellow diamonds are produced by high pressure high temperature method. Gem quality stones are relatively clean. Analytical / standard techniques may be required to identify the stones.
Glass
- Hardness: 5.5
- Specific gravity: 3.70
- Refractive index: 1.60 – 1.66
- Optic sign: SR
- Birefringence: -
- Other points: Color, soft, inclusions (gas bubbles, swirls), luster, spectrum.
Assembled Stones
Doublets / Triplets
Corundum composites (natural crown/synthetic base)
Refractive index: 1.76 – 1.77
Birefringence: DR; 0.008
Other points: Immersion (Look for differences in color and luster between the sections)
Garnet topped doublet (glass)
- Refractive index: 1.76 +
- Optic sign: SR/ADR
- Birefringence: -
- Other points: Look for differences in color and luster between the sections, gas bubbles)
- Determine optic character: Single refractive (SR) / Double refractive (DR) / Anomalous Double refractive (ADR) / Aggregate (AGG).
- Spectrum: Many yellow stones may have diagnostic spectrum.
- Microscope: Inclusions may be diagnostic, but look for inclusions that differentiate natural and synthetic, doublet / triplet.
- Dichroscope: Different cutting orientations of natural and synthetic corundum may be revealed by dichroscope.
- Fluorescence: Look under shortwave and longwave for diagnostic colors.
- Immersion cell: Use immersion cell and high refractive index liquid to separate doublets/triplets.
- Refractometer: Confirm spectroscope reading with refractometer.
The yellow stones, which may resemble one another in appearance and values, are:
Quartz, Citrine
- Hardness: 7
- Specific gravity: 2.65
- Refractive index: 1.54 – 1.55
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.009
- Other points: Color, inclusions. Citrine may be treated. Gem quality stones are relatively clean. Common look-alikes are yellow beryl, yellow labradorite, scapolite, and glass. Standard / analytical techniques may be required to detect treatments / identify stones.
Synthetic quartz , citrine
- Hardness: 7
- Specific gravity: 2.65
- Refractive index: 1.54 – 1.55
- Optic sign: Uniaxial positive
- Birefringence: DR; 0.009
- Other points: Color, inclusions, twinning pattern. Synthetic citrine is produced by the hydrothermal process. Gem quality stones are relatively clean. Standard / analytical techniques may be required to identify stones.
Feldspar, Orthoclase
- Hardness: 6
- Specific gravity: 2.56
- Refractive index: 1.52 – 1.53
- Optic sign: Biaxial negative
- Birefringence: DR; 0.006
- Other points: Color, inclusions, cleavage. Gem quality stones are relatively clean. Common look-alikes are yellow beryl, citrine, scapolite, and glass. Standard / analytical techniques may be required to identify stones.
Feldspar, Labradorite
- Hardness: 6
- Specific gravity: 2.70 (average)
- Refractive index: 1.56 – 1.57
- Optic sign: Biaxial positive
- Birefringence: DR; 0.009
- Other points: Color, inclusions, cleavage. Gem quality stones are relatively clean. Common look-alikes are yellow beryl, citrine, scapolite, and glass. Standard / analytical techniques may be required to identify stones.
Beryl
- Hardness: 7.75
- Specific gravity: 2.70 – 2.90
- Refractive index: 1.56 – 1.59
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.005/9
- Other points: Color, inclusions. Gem quality stones are relatively clean. Yellow beryl may treated. Common look-alikes are yellow labradorite, citrine, scapolite, and glass. Standard / analytical techniques may be required to identify stones.
Scapolite
- Hardness: 6
- Specific gravity: 2.50-2.70
- Refractive index: 1.54 – 1.58
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.009 - 026
- Other points: Color, inclusions, fluorescence. Gem quality stones are relatively clean. Common look-alikes are yellow labradorite, citrine, yellow beryl, and glass. Standard / analytical techniques may be required to identify stones.
Apatite
- Hardness: 5
- Specific gravity: 3.18
- Refractive index: 1.63 – 1.64
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.002 – 0.004
- Other points: Color, inclusions, spectrum. Apatite may be treated. Gem quality stones are relatively clean. Common imitations include chrysoberyl, sapphire, tourmaline, danburite, peridot, topaz and glass. Standard / analytical techniques may be required to identify stones.
Danburite
- Hardness: 7
- Specific gravity: 3.00
- Refractive index: 1.63 – 1.64
- Optic sign: Biaxial negative
- Birefringence: DR; 0.006
- Other points: Color, inclusions, spectrum. Gem quality stones are relatively clean. Common imitations include chrysoberyl, sapphire, tourmaline, apatite, peridot, topaz and glass. Standard / analytical techniques may be required to identify stones.
Topaz
- Hardness: 8
- Specific gravity: 3.53
- Refractive index: 1.63 – 1.64
- Optic sign: Biaxial positive
- Birefringence: DR; 0.008
- Other points: Color, inclusions, cleavage. Topaz may be treated. Gem quality stones are relatively clean. Common imitations include chrysoberyl, sapphire, tourmaline, apatite, peridot, danburite and glass. Standard / analytical techniques may be required to detect treatments / identify stones.
Tourmaline
- Hardness: 7
- Specific gravity: 3.05
- Refractive index: 1.62 – 1.64
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.018
- Other points: Color, inclusions, doubling of back facets, pleochroism. Tourmaline may be treated. Gem quality stones are relatively clean. Common imitations include chrysoberyl, sapphire, topaz, apatite, peridot, danburite and glass. Standard / analytical techniques may be required to detect treatments / identify stones.
Idocrase
- Hardness: 6.5
- Specific gravity: 3.35
- Refractive index: 1.70 – 1.73
- Optic sign: Uniaxial negative / positive
- Birefringence: DR; 0.005
- Other points: Color, spectrum. Common imitations include chrysoberyl, sapphire, topaz, apatite, peridot, danburite, tourmaline, and glass. Standard / analytical techniques may be required to detect treatments / identify stones.
Grossular garnet
- Hardness: 7.25
- Specific gravity: 3.60 – 3.70
- Refractive index: 1.74 – 1.75
- Optic sign: SR
- Birefringence: -
- Other points: Color, inclusions. Gem quality stones are relatively clean. Common imitations include chrysoberyl, sapphire, topaz, apatite, peridot, danburite, tourmaline, and glass. Standard / analytical techniques may be required to detect treatments / identify stones.
Chrysoberyl
- Hardness: 8.5
- Specific gravity: 3.72
- Refractive index: 1.74 – 1.75
- Optic sign: Biaxial positive
- Birefringence: DR; 0.009
- Other points: Color, inclusions, spectrum. Chrysoberyl may be treated. Gem quality stones are relatively clean. Common imitations include idocrase, hessonite garnet, sapphire, topaz, apatite, peridot, danburite, tourmaline, and glass. Standard / analytical techniques may be required to detect treatments / identify stones.
Sapphire
- Hardness: 9
- Specific gravity: 4
- Refractive index: 1.76 – 1.77
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.008
- Other points: Color, inclusions, spectrum. Yellow sapphire may be treated. Gem quality stones are relatively clean. Common imitations include chrysoberyl, idocrase, hessonite garnet, topaz, apatite, peridot, danburite, tourmaline, and glass. Standard / analytical techniques may be required to detect treatments / identify stones.
Andradite garnet (yellow demantoid)
- Hardness: 6.5
- Specific gravity: 3.85
- Refractive index: 1.89
- Optic sign: SR
- Birefringence: -
- Other points: Color, inclusions, negative refractive index reading, spectrum, dispersion, luster. Common imitations include chrysoberyl, idocrase, sapphire, topaz, apatite, peridot, danburite, tourmaline, zircon, sphene, and glass. Standard / analytical techniques may be required to detect treatments / identify stones.
Zircon
- Hardness: 7.5
- Specific gravity: 4.69
- Refractive index: 1.93 – 1.99
- Optic sign: Uniaxial positive
- Birefringence: DR; 0.059
- Other points: Color, inclusions, doubling of back facets, spectrum, luster. Zircon may be treated. Gem quality stones are relatively clean. Common imitations include chrysoberyl, idocrase, sapphire, topaz, apatite, peridot, danburite, tourmaline, demantoid garnet, sphene and glass. Standard / analytical techniques may be required to detect treatments / identify stones.
Sphene
- Hardness: 5.5
- Specific gravity: 3.53
- Refractive index: 1.89 – 2.02
- Optic sign: Biaxial positive
- Birefringence: DR; 0.051
- Other points: Color, negative refractive index reading, dispersion, doubling of back facets, spectrum. Common imitations include chrysoberyl, idocrase, sapphire, topaz, apatite, peridot, danburite, tourmaline, zircon, demantoid garnet and glass. Standard / analytical techniques may be required to detect treatments / identify stones.
Synthetic cubic zirconia
- Hardness: 8.5
- Specific gravity: 5.65+
- Refractive index: 2.15+
- Optic sign: SR
- Birefringence: -
- Other points: Color, inclusions, negative refractive index, luster, dispersion, orange flash on the pavilion. Most gem quality stones are relatively clean. High dispersion will easily identify the stone. Standard / analytical techniques may be required to identify stones.
Diamond
- Hardness: 10
- Specific gravity: 3.52
- Refractive index: 2.42
- Optic sign: SR/ADR
- Birefringence: -
- Other points: Color, negative refractive index reading, dispersion, spectrum, inclusions. Yellow diamonds may be treated. Gem quality stones are relatively clean. Common imitations are synthetic cubic zirconia, synthetic moissanite, synthetic strontium titanate, GGG and glass. Analytical / standard techniques may be required to detect treatments / identify the stones.
Synthetic diamond
- Hardness: 10
- Specific gravity: 3.52
- Refractive index: 2.42
- Optic sign: SR/ADR
- Birefringence: -
- Other points: Color, negative refractive index reading, dispersion, spectrum, inclusions. Synthetic yellow diamonds are produced by high pressure high temperature method. Gem quality stones are relatively clean. Analytical / standard techniques may be required to identify the stones.
Glass
- Hardness: 5.5
- Specific gravity: 3.70
- Refractive index: 1.60 – 1.66
- Optic sign: SR
- Birefringence: -
- Other points: Color, soft, inclusions (gas bubbles, swirls), luster, spectrum.
Assembled Stones
Doublets / Triplets
Corundum composites (natural crown/synthetic base)
Refractive index: 1.76 – 1.77
Birefringence: DR; 0.008
Other points: Immersion (Look for differences in color and luster between the sections)
Garnet topped doublet (glass)
- Refractive index: 1.76 +
- Optic sign: SR/ADR
- Birefringence: -
- Other points: Look for differences in color and luster between the sections, gas bubbles)
Patience And Discipline
Forbes writes:
Mary Buffett spoke to Forbes.com about patience, discipline and Warren Buffett's pleasure dome.
Forbes.com: What's the most important lesson you've learned from Warren Buffett?
Mary Buffett: Patience and discipline. And doing something you love. So many people -- and Warren has said this -- are doing it for the money. That's really not the right reason. If you're doing something you love, you're more likely to put your all into it, and that generally equates to making money. He always says when he gets up in the morning he goes to his pleasure dome, which is his office.
Mary Buffett spoke to Forbes.com about patience, discipline and Warren Buffett's pleasure dome.
Forbes.com: What's the most important lesson you've learned from Warren Buffett?
Mary Buffett: Patience and discipline. And doing something you love. So many people -- and Warren has said this -- are doing it for the money. That's really not the right reason. If you're doing something you love, you're more likely to put your all into it, and that generally equates to making money. He always says when he gets up in the morning he goes to his pleasure dome, which is his office.
Monday, January 22, 2007
Color
Edited by Helen Varley
The Knapp Press, Publishers, Los Angeles
The Viking Press, Distributors, New York
1980 ISBN 0-89535-037-8
The Knapp Press writes:
Color is simply the greatest show on earth. Every moment it floods us with information and sensation, delineating everything we see—even our dreams. We use it in countless ways to express ourselves and to assess others. Color reaches the heart, mind and spirit alike. It can be the visceral thrill of scarlet uniform; the pleasure of a Picasso painting; the soul-solace of a violet twilight sky. Some 10,000,000 variations of color may be distinguished by the human eye. For sheer dynamic range, no other medium can touch it. Color is among the richest experiences our sense offer.
But what is color? To the physicist it is light; to the chemist it is dye or pigments. To the physiologist it exists only in the eye of the beholder; and to the psychologist color perception is a function of the brain. Color is universally present, yet its true nature is elusive. The attempt to comprehend it has obsessed some of the greatest minds in history; Aristotle, Newton and Goethe are among those who developed detailed color theories.
A fair measure of every civilization has been the passion and ingenuity with which it has sought and used color. The formulations of certain dyes and pigments were so jealously guarded that their disclosure was punishable by death. The dazzling rise of color technology means that we now live in an age of unprecedented ‘color plenty’. Trade and industry, advertisers and packagers, update their color research constantly, so crucial to profit is the right color. Prodigious choice has also bred more discriminating consumers, eager to learn about the many ways color can improve the quality of life.
Universally present, color is too often taken for granted, its possibilities scarcely tapped. People fall into comfortable patterns with clothes, cosmetics and décor, hesitating to expand safe, small circles of color. To them red means warmth, blue means cold. It is easier to feel than to think about. Yet the rewards of experimentation can be spectacular.
The fresh insights provided by Color help you to manage this powerful source for maximum satisfaction. By understanding how colors relate to one another, and to you personally, you can improve your appearance, and surroundings, enhance your sense of well being and do justice to your individuality.
Color is unique tool for raising your color consciousness. Never before has one volume presented the subject from such diverse angles, providing the ideal basis for both an immediate and lifelong study. Color’s bonus is the way in which the whole exceeds the sum of its very handsome parts. When the relations of physics to art to fashion to psychology gradually coalesce, your perception is enhanced as if your eyes had been reborn. Everyday sights are charged with a new, unimaginably richer, dimension. After Color your world will never look the same again.
The Knapp Press, Publishers, Los Angeles
The Viking Press, Distributors, New York
1980 ISBN 0-89535-037-8
The Knapp Press writes:
Color is simply the greatest show on earth. Every moment it floods us with information and sensation, delineating everything we see—even our dreams. We use it in countless ways to express ourselves and to assess others. Color reaches the heart, mind and spirit alike. It can be the visceral thrill of scarlet uniform; the pleasure of a Picasso painting; the soul-solace of a violet twilight sky. Some 10,000,000 variations of color may be distinguished by the human eye. For sheer dynamic range, no other medium can touch it. Color is among the richest experiences our sense offer.
But what is color? To the physicist it is light; to the chemist it is dye or pigments. To the physiologist it exists only in the eye of the beholder; and to the psychologist color perception is a function of the brain. Color is universally present, yet its true nature is elusive. The attempt to comprehend it has obsessed some of the greatest minds in history; Aristotle, Newton and Goethe are among those who developed detailed color theories.
A fair measure of every civilization has been the passion and ingenuity with which it has sought and used color. The formulations of certain dyes and pigments were so jealously guarded that their disclosure was punishable by death. The dazzling rise of color technology means that we now live in an age of unprecedented ‘color plenty’. Trade and industry, advertisers and packagers, update their color research constantly, so crucial to profit is the right color. Prodigious choice has also bred more discriminating consumers, eager to learn about the many ways color can improve the quality of life.
Universally present, color is too often taken for granted, its possibilities scarcely tapped. People fall into comfortable patterns with clothes, cosmetics and décor, hesitating to expand safe, small circles of color. To them red means warmth, blue means cold. It is easier to feel than to think about. Yet the rewards of experimentation can be spectacular.
The fresh insights provided by Color help you to manage this powerful source for maximum satisfaction. By understanding how colors relate to one another, and to you personally, you can improve your appearance, and surroundings, enhance your sense of well being and do justice to your individuality.
Color is unique tool for raising your color consciousness. Never before has one volume presented the subject from such diverse angles, providing the ideal basis for both an immediate and lifelong study. Color’s bonus is the way in which the whole exceeds the sum of its very handsome parts. When the relations of physics to art to fashion to psychology gradually coalesce, your perception is enhanced as if your eyes had been reborn. Everyday sights are charged with a new, unimaginably richer, dimension. After Color your world will never look the same again.
Tattoo Removal + Business
Here is an interesting article on tattoo removal. A few months ago I remember having an interesting conversation with a Swiss expert who is familiar with Laser Ablation Inductive Coupled Plasma Mass Spectroscopy and Laser Induced Breakdown Spectroscopy. He said that the instruments were not only capable of detecting light elements but also removing tattoos.
Rachael Barron writes:
Laser maker takes stake in ink developer as two pair up on tattoo removal.
There are things in life one can’t help but regret. Like that snake tattoo on a forearm that circles the name of an ex-girlfriend. The options: live with it, or go though a painful and expensive removal process.
Laser maker Candela hopes to change all that. The company said Thursday it will be adding to its arsenal of tattoo removal technology the development of a new light-based device. The device’s design will work in tandem with a specialized ink in development geared for easier tattoo removal.
The news underscores innovations that could benefit from a mess of tattoos going mainstream on Hollywood actors and NBA players in recent years.
It come as part of a deal signed with the ink’s developer, privately held Freedom-2. Candela also said it made an investment in the West Conshohocken, Pennsylvania-based ink maker, but financial details were undisclosed.
If all goes as planned, the combo should allow people with a change of heart the ability to remove a tattoo with a single laser treatment.
Much of the removal ability lies in Freedom-2’s ink. The ink is basically a micro-encapsulation of color pigments within colorless polymer beads. A single laser treatment is expected to break up the beads, allowing the body to naturally expel the dye.
It’s a way better alternative when one considers what’s currently available. The most common technique is laser surgery. Here, doctors pulse light through the top layer of skin, where the light’s energy is absorbed by the tattoo’s pigment and breaks down. The broken-down ink is then absorbed by the body.
But make no mistake, at least at this point, it’s not a one-time deal. Different lasers are more effective at removing certain colors or work better on different skin shades. As well, there is only so much laser energy the skin can tolerate in one sitting. As a result, it can take about six to 12 treatments to achieve removal. And the price can range from about $1,000, to $5,000 and beyond, depending on tattoo size and location.
About a quarter of adults age 18 to 50 in the United States have a tattoo, and almost 20 percent of them have debated removing it or covering it up, according to the Journal of the American Academy of Dermatology.
Candela already has one removal device on the market known for its abilities to clean away black, blue, and green tattoo pigments. It also is readying to unveil its next-generation model in February that the company says will remove an even wider palette of colors. The expected price tag is in the range of $85,000 to $150,000, according to equity research firm Maxim Group.
But perhaps such machines will gradually become a thing of the past with such breakthroughs as inks trying to be offered by Freedom-2.
The company has been testing its ink’s removal prowess, including on its CEO Martin Schmeig (now that’s devotion). Freedom-2 said it plans to have its ink on the market this year.
Candela’s stock rose $0.12 to $12.60 in recent trading.
More info @
http://www.redherring.com/Article.aspx?a=20818&hed=Tattoo+Removal%e2%80%99s+Investors
Rachael Barron writes:
Laser maker takes stake in ink developer as two pair up on tattoo removal.
There are things in life one can’t help but regret. Like that snake tattoo on a forearm that circles the name of an ex-girlfriend. The options: live with it, or go though a painful and expensive removal process.
Laser maker Candela hopes to change all that. The company said Thursday it will be adding to its arsenal of tattoo removal technology the development of a new light-based device. The device’s design will work in tandem with a specialized ink in development geared for easier tattoo removal.
The news underscores innovations that could benefit from a mess of tattoos going mainstream on Hollywood actors and NBA players in recent years.
It come as part of a deal signed with the ink’s developer, privately held Freedom-2. Candela also said it made an investment in the West Conshohocken, Pennsylvania-based ink maker, but financial details were undisclosed.
If all goes as planned, the combo should allow people with a change of heart the ability to remove a tattoo with a single laser treatment.
Much of the removal ability lies in Freedom-2’s ink. The ink is basically a micro-encapsulation of color pigments within colorless polymer beads. A single laser treatment is expected to break up the beads, allowing the body to naturally expel the dye.
It’s a way better alternative when one considers what’s currently available. The most common technique is laser surgery. Here, doctors pulse light through the top layer of skin, where the light’s energy is absorbed by the tattoo’s pigment and breaks down. The broken-down ink is then absorbed by the body.
But make no mistake, at least at this point, it’s not a one-time deal. Different lasers are more effective at removing certain colors or work better on different skin shades. As well, there is only so much laser energy the skin can tolerate in one sitting. As a result, it can take about six to 12 treatments to achieve removal. And the price can range from about $1,000, to $5,000 and beyond, depending on tattoo size and location.
About a quarter of adults age 18 to 50 in the United States have a tattoo, and almost 20 percent of them have debated removing it or covering it up, according to the Journal of the American Academy of Dermatology.
Candela already has one removal device on the market known for its abilities to clean away black, blue, and green tattoo pigments. It also is readying to unveil its next-generation model in February that the company says will remove an even wider palette of colors. The expected price tag is in the range of $85,000 to $150,000, according to equity research firm Maxim Group.
But perhaps such machines will gradually become a thing of the past with such breakthroughs as inks trying to be offered by Freedom-2.
The company has been testing its ink’s removal prowess, including on its CEO Martin Schmeig (now that’s devotion). Freedom-2 said it plans to have its ink on the market this year.
Candela’s stock rose $0.12 to $12.60 in recent trading.
More info @
http://www.redherring.com/Article.aspx?a=20818&hed=Tattoo+Removal%e2%80%99s+Investors
How To Separate Frequently Encountered Colorless Stones
- Visual observation: (10x lens) Look for color, luster, cut, doublet/triplet junctions, if any.
- Determine optic character: Single refractive (SR) / Double refractive (DR) / Anomalous Double refractive (ADR) / Aggregate (AGG).
- Spectrum: Many colorless stones may have diagnostic spectrum.
- Microscope: Inclusions may be diagnostic, but look for inclusions that differentiate natural and synthetic, doublet / triplet.
- Fluorescence: Look under shortwave and longwave for diagnostic colors.
- Immersion cell: Use immersion cell and high refractive index liquid to separate doublets/triplets.
- Refractometer: Confirm spectroscope reading with refractometer.
The colorless stones, which may resemble one another in appearance and values, are:
Diamond
- Hardness: 10
- Specific gravity: 3.52
- Refractive index: 2.42
- Optic sign: SR/ADR
- Birefringence: -
- Other points: negative refractive index, dispersion, luster, look at the girdle plane; cleavage, inclusions, weak to strong fluorescence in long wave (may be inert). Diamonds may be treated. Sapphire, synthetic sapphire, spinel, synthetic spinel, zircon, synthetic lithium niobate, synthetic rutile, synthetic yttrium aluminum garnet (YAG), synthetic gadolium gallium garnet (GGG), synthetic strontium titanate, synthetic cubic zircona (CZ), topaz, quartz, and glass may look like diamond. Standard / analytical techniques may be required to detect treatments / identify the stones.
Synthetic cubic zirconia
- Hardness: 8.5
- Specific gravity: 5.60 – 6.0
- Refractive index: 2.15 – 2.18 (average)
- Optic sign: SR
- Birefringence: -
- Other points: negative refractive index, dispersion, luster, orange flash on the pavilion, girdle, inclusions, fluorescence. Gem quality stones are relatively clean. Standard / analytical techniques may be required to identify the stones.
Synthetic strontium titanate
- Hardness: 5.5
- Specific gravity: 5.13
- Refractive index: 2.41
- Optic sign: SR
- Birefringence: -
- Other points: negative refractive index, dispersion, luster, girdle, inclusions, fluorescence, rounded facet edges. Gem quality stones are relatively clean. Standard / analytical techniques may be required to identify the stones.
Synthetic gadolium gallium garnet (GGG)
- Hardness: 6.5
- Specific gravity: 7.05
- Refractive index: 1.97
- Optic sign: SR
- Birefringence: -
- Other points: negative refractive index, dispersion, luster, girdle, color, inclusions, fluorescence (strong orange yellow (LW) and yellow (SW)), rounded facet edges. Gem quality stones are relatively clean. Standard / analytical techniques may be required to identify the stones.
Synthetic yttrium aluminum garnet (YAG)
- Hardness: 8.5
- Specific gravity: 4.58
- Refractive index: 1.83
- Optic sign: SR
- Birefringence: -
- Other points: negative refractive index, dispersion, luster, girdle, inclusions, fluorescence (variable). Gem quality stones are relatively clean. Standard / analytical techniques may be required to identify the stones.
Synthetic rutile
- Hardness: 6.5
- Specific gravity: 4.25
- Refractive index: 2.61 – 2.90
- Optic sign: Uniaxial positive
- Birefringence: DR; 0.287
- Other points: negative refractive index, strong dispersion, luster, doubling of back facets, inclusions, rounded facet edges. Gem quality stones are relatively clean. Standard / analytical techniques may be required to identify the stones.
Synthetic lithium niobate
- Hardness: 5.5
- Specific gravity: 4.64
- Refractive index: 2.21 – 2.30
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.09
- Other points: soft, negative refractive index, luster, inclusions. Gem quality stones are relatively clean. Standard / analytical techniques may be required to identify the stones.
Zircon (high type)
- Hardness: 7.5
- Specific gravity: 4.69
- Refractive index: 1.93 -1.99
- Optic sign: Uniaxial positive
- Birefringence: DR; 0.059
- Other points: dispersion, negative refractive index, luster, inclusions, doubling of back facets, spectrum. Gem quality stones are relatively clean. Standard / analytical techniques may be required to identify the stones.
Syntehic spinel
- Hardness: 8
- Specific gravity: 3.63
- Refractive index: 1.728
- Optic sign: SR/ADR
- Birefringence: -
- Other points: dispersion, vitreous, luster, inclusions, fluorescence. Gem quality stones are relatively clean. Standard / analytical techniques may be required to identify the stones.
Synthetic Moissanite
- Hardness: 9.25
- Specific gravity: 3.22
- Refractive index: 2.65-2.69
- Optic sign: DR
- Other points: Color, luster, fluorescence, inclusions, doubling of back facets. Gem quality stones are relatively clean. Standard / analytical techniques may be required to identify the stones.
Sapphire
- Hardness: 9
- Specific gravity: 4
- Refractive index: 1.76 – 1.77
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.008
- Other points: vitreous, luster, inclusions, fluorescence. Gem quality stones are relatively clean. Standard / analytical techniques may be required to identify the stones.
Synthetic white (colorless) sapphire
- Hardness: 9
- Specific gravity: 4
- Refractive index: 1.76 – 1.77
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.008
- Other points: vitreous, luster, inclusions, fluorescence. Gem quality stones are relatively clean. Standard / analytical techniques may be required to identify the stones.
Glass
- Hardness: 5.5
- Specific gravity: 3.70
- Refractive index: 1.60 – 1.66
- Optic sign: SR
- Birefringence: -
- Other points: Color, soft, inclusions (gas bubbles, swirls), luster, spectrum. Standard / analytical techniques may be required to identify the stones.
Assembled Stones
Doublets / Triplets
Diamond composites (diamond / diamond)
- Refractive index: 2.42
- Optic sign: SR/ADR
- Birefringence: -
- Other points: Immersion (Look for differences in color and luster between the sections), polishing marks.
Synthetic corundum or spinel on / synthetic strontium titanate
- Other points: Look for differences in color and luster between the sections, gas bubbles)
- Determine optic character: Single refractive (SR) / Double refractive (DR) / Anomalous Double refractive (ADR) / Aggregate (AGG).
- Spectrum: Many colorless stones may have diagnostic spectrum.
- Microscope: Inclusions may be diagnostic, but look for inclusions that differentiate natural and synthetic, doublet / triplet.
- Fluorescence: Look under shortwave and longwave for diagnostic colors.
- Immersion cell: Use immersion cell and high refractive index liquid to separate doublets/triplets.
- Refractometer: Confirm spectroscope reading with refractometer.
The colorless stones, which may resemble one another in appearance and values, are:
Diamond
- Hardness: 10
- Specific gravity: 3.52
- Refractive index: 2.42
- Optic sign: SR/ADR
- Birefringence: -
- Other points: negative refractive index, dispersion, luster, look at the girdle plane; cleavage, inclusions, weak to strong fluorescence in long wave (may be inert). Diamonds may be treated. Sapphire, synthetic sapphire, spinel, synthetic spinel, zircon, synthetic lithium niobate, synthetic rutile, synthetic yttrium aluminum garnet (YAG), synthetic gadolium gallium garnet (GGG), synthetic strontium titanate, synthetic cubic zircona (CZ), topaz, quartz, and glass may look like diamond. Standard / analytical techniques may be required to detect treatments / identify the stones.
Synthetic cubic zirconia
- Hardness: 8.5
- Specific gravity: 5.60 – 6.0
- Refractive index: 2.15 – 2.18 (average)
- Optic sign: SR
- Birefringence: -
- Other points: negative refractive index, dispersion, luster, orange flash on the pavilion, girdle, inclusions, fluorescence. Gem quality stones are relatively clean. Standard / analytical techniques may be required to identify the stones.
Synthetic strontium titanate
- Hardness: 5.5
- Specific gravity: 5.13
- Refractive index: 2.41
- Optic sign: SR
- Birefringence: -
- Other points: negative refractive index, dispersion, luster, girdle, inclusions, fluorescence, rounded facet edges. Gem quality stones are relatively clean. Standard / analytical techniques may be required to identify the stones.
Synthetic gadolium gallium garnet (GGG)
- Hardness: 6.5
- Specific gravity: 7.05
- Refractive index: 1.97
- Optic sign: SR
- Birefringence: -
- Other points: negative refractive index, dispersion, luster, girdle, color, inclusions, fluorescence (strong orange yellow (LW) and yellow (SW)), rounded facet edges. Gem quality stones are relatively clean. Standard / analytical techniques may be required to identify the stones.
Synthetic yttrium aluminum garnet (YAG)
- Hardness: 8.5
- Specific gravity: 4.58
- Refractive index: 1.83
- Optic sign: SR
- Birefringence: -
- Other points: negative refractive index, dispersion, luster, girdle, inclusions, fluorescence (variable). Gem quality stones are relatively clean. Standard / analytical techniques may be required to identify the stones.
Synthetic rutile
- Hardness: 6.5
- Specific gravity: 4.25
- Refractive index: 2.61 – 2.90
- Optic sign: Uniaxial positive
- Birefringence: DR; 0.287
- Other points: negative refractive index, strong dispersion, luster, doubling of back facets, inclusions, rounded facet edges. Gem quality stones are relatively clean. Standard / analytical techniques may be required to identify the stones.
Synthetic lithium niobate
- Hardness: 5.5
- Specific gravity: 4.64
- Refractive index: 2.21 – 2.30
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.09
- Other points: soft, negative refractive index, luster, inclusions. Gem quality stones are relatively clean. Standard / analytical techniques may be required to identify the stones.
Zircon (high type)
- Hardness: 7.5
- Specific gravity: 4.69
- Refractive index: 1.93 -1.99
- Optic sign: Uniaxial positive
- Birefringence: DR; 0.059
- Other points: dispersion, negative refractive index, luster, inclusions, doubling of back facets, spectrum. Gem quality stones are relatively clean. Standard / analytical techniques may be required to identify the stones.
Syntehic spinel
- Hardness: 8
- Specific gravity: 3.63
- Refractive index: 1.728
- Optic sign: SR/ADR
- Birefringence: -
- Other points: dispersion, vitreous, luster, inclusions, fluorescence. Gem quality stones are relatively clean. Standard / analytical techniques may be required to identify the stones.
Synthetic Moissanite
- Hardness: 9.25
- Specific gravity: 3.22
- Refractive index: 2.65-2.69
- Optic sign: DR
- Other points: Color, luster, fluorescence, inclusions, doubling of back facets. Gem quality stones are relatively clean. Standard / analytical techniques may be required to identify the stones.
Sapphire
- Hardness: 9
- Specific gravity: 4
- Refractive index: 1.76 – 1.77
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.008
- Other points: vitreous, luster, inclusions, fluorescence. Gem quality stones are relatively clean. Standard / analytical techniques may be required to identify the stones.
Synthetic white (colorless) sapphire
- Hardness: 9
- Specific gravity: 4
- Refractive index: 1.76 – 1.77
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.008
- Other points: vitreous, luster, inclusions, fluorescence. Gem quality stones are relatively clean. Standard / analytical techniques may be required to identify the stones.
Glass
- Hardness: 5.5
- Specific gravity: 3.70
- Refractive index: 1.60 – 1.66
- Optic sign: SR
- Birefringence: -
- Other points: Color, soft, inclusions (gas bubbles, swirls), luster, spectrum. Standard / analytical techniques may be required to identify the stones.
Assembled Stones
Doublets / Triplets
Diamond composites (diamond / diamond)
- Refractive index: 2.42
- Optic sign: SR/ADR
- Birefringence: -
- Other points: Immersion (Look for differences in color and luster between the sections), polishing marks.
Synthetic corundum or spinel on / synthetic strontium titanate
- Other points: Look for differences in color and luster between the sections, gas bubbles)
The Art Of Faberge
By A Kenneth Snowman
New York Graphic Society Ltd, Greenwich, Connecticut, USA
ISBN 0-8212-0609-5
1953 / 1962
New York Graphic Society writes:
Carl Faberge, goldsmith and jeweler to the Imperial Court of Russia in the years before First World War, was a consummate craftsman, a virtuoso artist in the design and production of exquisite objects. It was his good fortune and ours, comments the author of this magnificently illustrated study of his work, that he was born into an age still able to afford him. When the new Soviet government took over control of private business after the war, Faberge himself is said to have asked, with characteristic lack of ceremony, for ten minutes grace ‘to put on my hat and coat’. He died in Lausanne in 1920, an exile from his country and his work.
The photographs in this volume include a selection from the collection of the Kremlin Museums of the fabulous Imperial Easter Eggs presented each year to Tsarinas, and objects from the British Royal Collections at Sandringham, from other museums, and from the most important private collection in the United States: jewelry, flower studies and animal carvings in semi-precious stones, a dazzling assembly of snuff boxes, cigarette cases, parasol handles, inkwells, clocks and lorgnettes, chess sets and letter openers.
New York Graphic Society Ltd, Greenwich, Connecticut, USA
ISBN 0-8212-0609-5
1953 / 1962
New York Graphic Society writes:
Carl Faberge, goldsmith and jeweler to the Imperial Court of Russia in the years before First World War, was a consummate craftsman, a virtuoso artist in the design and production of exquisite objects. It was his good fortune and ours, comments the author of this magnificently illustrated study of his work, that he was born into an age still able to afford him. When the new Soviet government took over control of private business after the war, Faberge himself is said to have asked, with characteristic lack of ceremony, for ten minutes grace ‘to put on my hat and coat’. He died in Lausanne in 1920, an exile from his country and his work.
The photographs in this volume include a selection from the collection of the Kremlin Museums of the fabulous Imperial Easter Eggs presented each year to Tsarinas, and objects from the British Royal Collections at Sandringham, from other museums, and from the most important private collection in the United States: jewelry, flower studies and animal carvings in semi-precious stones, a dazzling assembly of snuff boxes, cigarette cases, parasol handles, inkwells, clocks and lorgnettes, chess sets and letter openers.
How To Avoid Mistakes
Warren Edward Buffett, CEO, Berkshire Hathaway writes:
'What counts for most people in investing is not how much they know, but rather how realistically they define what they don't know. An investor needs to do very few things right as long as he or she avoids big mistakes.'
'What counts for most people in investing is not how much they know, but rather how realistically they define what they don't know. An investor needs to do very few things right as long as he or she avoids big mistakes.'
How To Separate Frequently Encountered Blue Stones
- Visual observation: (10x lens) Look for color, luster, cut, doublet/triplet junctions, if any.
- Determine optic character: Single refractive (SR) / Double refractive (DR) / Anomalous Double
refractive (ADR) / Aggregate (AGG).
- Spectrum: Many blue stones may have diagnostic spectrum.
- Microscope: Inclusions may be diagnostic, but look for inclusions that differentiate natural and
synthetic, doublet / triplet.
- Dichroscope: Different cutting orientations of natural and synthetic corundum may be revealed by dichroscope.
- Fluorescence: Look under shortwave and longwave for diagnostic colors.
- Immersion cell: Use immersion cell and high refractive index liquid to separate doublets/triplets.
- Refractometer: Confirm spectroscope reading with refractometer.
The blue stones, which may resemble one another in appearance and values, are:
Synthetic blue quartz
- Hardness: 7
- Specific gravity: 2.65
- Refractive index: 1.54 – 1.55
- Optic sign: Uniaxial positive
- Birefringence: DR; 0.009
- Other points: Color, inclusions, interference figures, if seen, spectrum. Common look-alikes include aquamarine, blue spinel, blue sapphire, blue topaz, and glass. Standard / analytical techniques may be required to identify the stones.
Iolite
- Hardness: 7.5
- Specific gravity: 2.60
- Refractive index: 1.54 – 1.55
- Optic sign: Biaxial negative
- Birefringence: DR; 0.009
- Other points: Color, pleochroism, inclusions. Iolite may be treated. Common look-alikes include amethyst, tanzanite, blue sapphire, blue spinel, blue tourmaline, tanzanite and glass. Standard / analytical techniques may be required to identify the stones.
Beryl (aquamarine)
- Hardness: 7.75
- Specific gravity: 2.70-2.90
- Refractive index: 1.56 – 1.59
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.005/9
- Other points: Color, inclusions. Aquamarine may be treated. Common look-alikes include blue topaz and glass. Standard / analytical techniques may be required to identify the stones.
Beryl (maxixe-type)
- Hardness: 8
- Specific gravity: 2.70 – 2.90
- Refractive index: 1.56 – 1.59
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.005/9
- Other points: Color (unstable color; fades), inclusions. Maxixe type beryl may be treated, and may look like aquamarine, tanzanite, synthetic blue quartz, and glass. Standard / analytical techniques may be required to detect treatments / identify the stones.
Blue topaz
- Hardness: 8
- Specific gravity: 3.56
- Refractive index: 1.61 – 1.62
- Optic sign: Biaxial positive
- Birefringence: DR; 0.010
- Other points: Color. Blue topaz may be treated. Most gem quality stones are relatively clean. Blue topaz may look like aquamarine, blue sapphire, blue spinel, iolite, synthetic blue quartz and glass. Standard / analytical techniques may be required to detect treatments / identify the stones.
Apatite
- Hardness: 5
- Specific gravity: 3.18
- Refractive index: 1.63 – 1.64
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.002- 4 (average)
- Other points: Color, spectrum, dichroism, inclusions. Gem quality stones may be relatively clean. Apatite may look like blue spinel, blue sapphire, blue topaz, blue tourmaline, and glass. Standard / analytical techniques may be required to identify the stones.
Tourmaline
- Hardness: 7
- Specific gravity: 3.05
- Refractive index: 1.62 – 1.64
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.018
- Other points: Color, inclusions, pleochroism, doubling of back facets. Tourmaline may be treated. Gem quality stones are relatively clean. Common look-alikes include blue sapphire, blue spinel, apatite, blue topaz, tanzanite, iolite and glass. Standard / analytical techniques may be required to detect treatments / identify the stones.
Tanzanite (Zoisite)
- Hardness: 6.5
- Specific gravity: 3.35
- Refractive index: 1.69 – 1.70
- Optic sign: Biaxial positive
- Birefringence: DR; 0.009
- Other points: Color, pleochroism, inclusions. Tanzanites may be treated. Gem quality stones relatively clean. Common look-alikes include blue sapphire, iolite, tourmaline, amethyst and glass. Standard / analytical techniques may be required to detect treatments / identify the stones.
Spinel
- Hardness: 8
- Specific gravity: 3.60+
- Refractive index: 1.718
- Optic sign: SR
- Birefringence: -
- Other points: Color, spectrum, inclusions. Gem quality blue spinels may be clean. Common look-alikes include blue sapphire, blue tourmaline, iolite, tanzanite, amethyst and glass. Standard / analytical techniques may be required to identify the stones.
Synthetic blue spinel
- Hardness: 8
- Specific gravity: 3.63
- Refractive index: 1.728
- Optic sign: SR
- Birefringence: -
- Other points: Color, inclusions, Chelsea color filter, fluorescence. Standard identification techniques may be required to identify the stones.
Sapphire
- Hardness: 9
- Specific gravity: 4
- Refractive index: 1.76 – 1.77
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.008
- Other points: Color, inclusions, fluorescence, spectrum. Use microscope to separate natural from synthetic. Sapphires may be treated. Gem quality stones are relatively clean. Common look- alikes include tanzanite, blue spinel, blue topaz, blue tourmaline, synthetic blue quartz, iolite and glass. Standard / analytical techniques may be required to detect treatments / identify the stones.
Synthetic sapphire
- Hardness: 9
- Specific gravity: 4
- Refractive index: 1.76 – 1.77
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.008
- Other points: Color, inclusions, fluorescence, spectrum. Use microscope to separate flame fusion from flux from hydrothermal stones. Gem quality stones are relatively clean. Analytical techniques may be required to identify the stones.
Benitoite
- Hardness: 6.5
- Specific gravity: 3.67
- Refractive index: 1.76 – 1.80
- Optic sign: Uniaxial positive
- Birefringence: DR; 0.047
- Other points: Color, inclusions, fluorescence, spectrum, dispersion. Standard / analytical techniques may be required to identify the stones.
Blue zircon
- Hardness: 7.5
- Specific gravity: 4.69
- Refractive index: 1.93 – 1.99
- Optic sign: Uniaxial positive
- Birefringence: DR; 0.059
- Other points: Color, inclusions, spectrum, doubling of back facets, negative refractive index reading, luster, abraded facet junctions. Common look-alikes include blue sapphire, blue topaz, aquamarine, synthetic blue quartz and glass. Gem quality stones are relatively clean. Standard / analytical techniques may be required to detect treatments / identify the stones.
Blue diamond
- Hardness: 10
- Specific gravity: 3.52
- Refractive index: 2.42
- Optic sign: SR/ADR
- Birefringence: -
- Other points: Rare; Color, inclusions, fluorescence, spectrum. Blue diamonds may be treated. Gem quality stones are relatively clean. Analytical techniques may be required to detect treatments.
Synthetic blue diamond
- Hardness: 10
- Specific gravity: 3.52
- Refractive index: 2.42
- Optic sign: SR/ADR
- Birefringence: -
- Other points: Color, inclusions, fluorescence, spectrum. Synthetic blue diamonds are produced by high pressure high temperature method. Gem quality stones are relatively clean. Analytical techniques may be required to identify the stones.
Synthetic blue cubic zirconia
- Hardness: 8.5
- Specific gravity: 5.65 +
- Refractive index: 2.15 +
- Optic sign: SR
- Birefringence: -
- Other points: Color, negative refractive index reading, luster, dispersion. Standard / analytical techniques may be required to identify the stones.
Glass
- Hardness: 5.5
- Specific gravity: 3.70
- Refractive index: 1.60 – 1.66
- Optic sign: SR
- Birefringence: -
- Other points: Color, soft, inclusions (gas bubbles, swirls), luster, Chelsea color filter (for cobalt rich stones), spectrum. Standard / analytical techniques may be required to identify the stones.
Assembled Stones
Doublets / Triplets
Corundum composites (natural crown/synthetic base)
Refractive index: 1.76 – 1.77
Birefringence: DR; 0.008
Other points: Immersion (Look for differences in color and luster between the sections)
Synthetic spinel soude (spinel / spinel)
- Refractive index: 1.728
- Optic sign: SR/ADR
- Birefringence: -
- Other points: Look for differences in color and luster between the sections, gas bubbles)
Garnet topped doublet (glass)
- Refractive index: 1.76 +
- Optic sign: SR/ADR
- Birefringence: -
- Other points: Look for differences in color and luster between the sections, gas bubbles)
- Determine optic character: Single refractive (SR) / Double refractive (DR) / Anomalous Double
refractive (ADR) / Aggregate (AGG).
- Spectrum: Many blue stones may have diagnostic spectrum.
- Microscope: Inclusions may be diagnostic, but look for inclusions that differentiate natural and
synthetic, doublet / triplet.
- Dichroscope: Different cutting orientations of natural and synthetic corundum may be revealed by dichroscope.
- Fluorescence: Look under shortwave and longwave for diagnostic colors.
- Immersion cell: Use immersion cell and high refractive index liquid to separate doublets/triplets.
- Refractometer: Confirm spectroscope reading with refractometer.
The blue stones, which may resemble one another in appearance and values, are:
Synthetic blue quartz
- Hardness: 7
- Specific gravity: 2.65
- Refractive index: 1.54 – 1.55
- Optic sign: Uniaxial positive
- Birefringence: DR; 0.009
- Other points: Color, inclusions, interference figures, if seen, spectrum. Common look-alikes include aquamarine, blue spinel, blue sapphire, blue topaz, and glass. Standard / analytical techniques may be required to identify the stones.
Iolite
- Hardness: 7.5
- Specific gravity: 2.60
- Refractive index: 1.54 – 1.55
- Optic sign: Biaxial negative
- Birefringence: DR; 0.009
- Other points: Color, pleochroism, inclusions. Iolite may be treated. Common look-alikes include amethyst, tanzanite, blue sapphire, blue spinel, blue tourmaline, tanzanite and glass. Standard / analytical techniques may be required to identify the stones.
Beryl (aquamarine)
- Hardness: 7.75
- Specific gravity: 2.70-2.90
- Refractive index: 1.56 – 1.59
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.005/9
- Other points: Color, inclusions. Aquamarine may be treated. Common look-alikes include blue topaz and glass. Standard / analytical techniques may be required to identify the stones.
Beryl (maxixe-type)
- Hardness: 8
- Specific gravity: 2.70 – 2.90
- Refractive index: 1.56 – 1.59
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.005/9
- Other points: Color (unstable color; fades), inclusions. Maxixe type beryl may be treated, and may look like aquamarine, tanzanite, synthetic blue quartz, and glass. Standard / analytical techniques may be required to detect treatments / identify the stones.
Blue topaz
- Hardness: 8
- Specific gravity: 3.56
- Refractive index: 1.61 – 1.62
- Optic sign: Biaxial positive
- Birefringence: DR; 0.010
- Other points: Color. Blue topaz may be treated. Most gem quality stones are relatively clean. Blue topaz may look like aquamarine, blue sapphire, blue spinel, iolite, synthetic blue quartz and glass. Standard / analytical techniques may be required to detect treatments / identify the stones.
Apatite
- Hardness: 5
- Specific gravity: 3.18
- Refractive index: 1.63 – 1.64
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.002- 4 (average)
- Other points: Color, spectrum, dichroism, inclusions. Gem quality stones may be relatively clean. Apatite may look like blue spinel, blue sapphire, blue topaz, blue tourmaline, and glass. Standard / analytical techniques may be required to identify the stones.
Tourmaline
- Hardness: 7
- Specific gravity: 3.05
- Refractive index: 1.62 – 1.64
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.018
- Other points: Color, inclusions, pleochroism, doubling of back facets. Tourmaline may be treated. Gem quality stones are relatively clean. Common look-alikes include blue sapphire, blue spinel, apatite, blue topaz, tanzanite, iolite and glass. Standard / analytical techniques may be required to detect treatments / identify the stones.
Tanzanite (Zoisite)
- Hardness: 6.5
- Specific gravity: 3.35
- Refractive index: 1.69 – 1.70
- Optic sign: Biaxial positive
- Birefringence: DR; 0.009
- Other points: Color, pleochroism, inclusions. Tanzanites may be treated. Gem quality stones relatively clean. Common look-alikes include blue sapphire, iolite, tourmaline, amethyst and glass. Standard / analytical techniques may be required to detect treatments / identify the stones.
Spinel
- Hardness: 8
- Specific gravity: 3.60+
- Refractive index: 1.718
- Optic sign: SR
- Birefringence: -
- Other points: Color, spectrum, inclusions. Gem quality blue spinels may be clean. Common look-alikes include blue sapphire, blue tourmaline, iolite, tanzanite, amethyst and glass. Standard / analytical techniques may be required to identify the stones.
Synthetic blue spinel
- Hardness: 8
- Specific gravity: 3.63
- Refractive index: 1.728
- Optic sign: SR
- Birefringence: -
- Other points: Color, inclusions, Chelsea color filter, fluorescence. Standard identification techniques may be required to identify the stones.
Sapphire
- Hardness: 9
- Specific gravity: 4
- Refractive index: 1.76 – 1.77
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.008
- Other points: Color, inclusions, fluorescence, spectrum. Use microscope to separate natural from synthetic. Sapphires may be treated. Gem quality stones are relatively clean. Common look- alikes include tanzanite, blue spinel, blue topaz, blue tourmaline, synthetic blue quartz, iolite and glass. Standard / analytical techniques may be required to detect treatments / identify the stones.
Synthetic sapphire
- Hardness: 9
- Specific gravity: 4
- Refractive index: 1.76 – 1.77
- Optic sign: Uniaxial negative
- Birefringence: DR; 0.008
- Other points: Color, inclusions, fluorescence, spectrum. Use microscope to separate flame fusion from flux from hydrothermal stones. Gem quality stones are relatively clean. Analytical techniques may be required to identify the stones.
Benitoite
- Hardness: 6.5
- Specific gravity: 3.67
- Refractive index: 1.76 – 1.80
- Optic sign: Uniaxial positive
- Birefringence: DR; 0.047
- Other points: Color, inclusions, fluorescence, spectrum, dispersion. Standard / analytical techniques may be required to identify the stones.
Blue zircon
- Hardness: 7.5
- Specific gravity: 4.69
- Refractive index: 1.93 – 1.99
- Optic sign: Uniaxial positive
- Birefringence: DR; 0.059
- Other points: Color, inclusions, spectrum, doubling of back facets, negative refractive index reading, luster, abraded facet junctions. Common look-alikes include blue sapphire, blue topaz, aquamarine, synthetic blue quartz and glass. Gem quality stones are relatively clean. Standard / analytical techniques may be required to detect treatments / identify the stones.
Blue diamond
- Hardness: 10
- Specific gravity: 3.52
- Refractive index: 2.42
- Optic sign: SR/ADR
- Birefringence: -
- Other points: Rare; Color, inclusions, fluorescence, spectrum. Blue diamonds may be treated. Gem quality stones are relatively clean. Analytical techniques may be required to detect treatments.
Synthetic blue diamond
- Hardness: 10
- Specific gravity: 3.52
- Refractive index: 2.42
- Optic sign: SR/ADR
- Birefringence: -
- Other points: Color, inclusions, fluorescence, spectrum. Synthetic blue diamonds are produced by high pressure high temperature method. Gem quality stones are relatively clean. Analytical techniques may be required to identify the stones.
Synthetic blue cubic zirconia
- Hardness: 8.5
- Specific gravity: 5.65 +
- Refractive index: 2.15 +
- Optic sign: SR
- Birefringence: -
- Other points: Color, negative refractive index reading, luster, dispersion. Standard / analytical techniques may be required to identify the stones.
Glass
- Hardness: 5.5
- Specific gravity: 3.70
- Refractive index: 1.60 – 1.66
- Optic sign: SR
- Birefringence: -
- Other points: Color, soft, inclusions (gas bubbles, swirls), luster, Chelsea color filter (for cobalt rich stones), spectrum. Standard / analytical techniques may be required to identify the stones.
Assembled Stones
Doublets / Triplets
Corundum composites (natural crown/synthetic base)
Refractive index: 1.76 – 1.77
Birefringence: DR; 0.008
Other points: Immersion (Look for differences in color and luster between the sections)
Synthetic spinel soude (spinel / spinel)
- Refractive index: 1.728
- Optic sign: SR/ADR
- Birefringence: -
- Other points: Look for differences in color and luster between the sections, gas bubbles)
Garnet topped doublet (glass)
- Refractive index: 1.76 +
- Optic sign: SR/ADR
- Birefringence: -
- Other points: Look for differences in color and luster between the sections, gas bubbles)
Gemstones
By Eduard Gubelin and Franz-Xaver Erni
2000 GeoScience Press Inc, Tucson, Arizona
ISBN 0-945005-36-9
GeoScience Press Inc writes:
This book offers the reader a deep insight into the fascinating world of gemstones. It provides an exact description of the individual gems and goes into their origins and their extraction. In this graphic style, Eduard Gubelin reports on the events deep inside the Earth aeons ago that led to the creation of these superlative, sparkling natural products and their colorful radiance. Even if these wonders of Nature can be reduced to chemical formulae, they nevertheless lose nothing of the fascination that they have had for humans since time immemorial.
Franz-Xaver Erni offers the reader a spellbinding tale of how gemstones have loyally accompanied humans throughout history. How gemstones have served women as jewelry and men as symbols of their power. The loveliest of gems adorn women’s jewelry as well as the crowns and insignia of worldly and spiritual rulers.
Throughout ages, individual gems have been allocated to the months of the year and to the signs of the zodiac and imbued with special healing powers in popular imagination. This book offers qualified answers to all questions relating to gemstones; it is not only an exciting read but also a reference work that can be consulted as required.
About the authors
Dr. Eduard J Gubelin is one of the foremost gemologists in the world.
Dr Franz-Xaver Erni is a freelance journalist (PEN).
2000 GeoScience Press Inc, Tucson, Arizona
ISBN 0-945005-36-9
GeoScience Press Inc writes:
This book offers the reader a deep insight into the fascinating world of gemstones. It provides an exact description of the individual gems and goes into their origins and their extraction. In this graphic style, Eduard Gubelin reports on the events deep inside the Earth aeons ago that led to the creation of these superlative, sparkling natural products and their colorful radiance. Even if these wonders of Nature can be reduced to chemical formulae, they nevertheless lose nothing of the fascination that they have had for humans since time immemorial.
Franz-Xaver Erni offers the reader a spellbinding tale of how gemstones have loyally accompanied humans throughout history. How gemstones have served women as jewelry and men as symbols of their power. The loveliest of gems adorn women’s jewelry as well as the crowns and insignia of worldly and spiritual rulers.
Throughout ages, individual gems have been allocated to the months of the year and to the signs of the zodiac and imbued with special healing powers in popular imagination. This book offers qualified answers to all questions relating to gemstones; it is not only an exciting read but also a reference work that can be consulted as required.
About the authors
Dr. Eduard J Gubelin is one of the foremost gemologists in the world.
Dr Franz-Xaver Erni is a freelance journalist (PEN).
Friday, January 19, 2007
The Great Book Of Jewels
By Ernst A and Jean Heiniger
Edita S.A, Lausanne, Switzerland
1974
ISBN 0-517-18132-0
Edita S.A writes:
Through all of the recorded history, jewels have exerted a powerful influence on affairs of men. The Great Book Of Jewels is the first book to capture all the history, romance, intrigue, and enduring beauty of precious stones, from their earliest history to present. The editors, Ernst and Jean Heiniger, aided by a team of nine distinguished gemologists from the world’s foremost museums have amassed a wealth of jewelry lore and scientific fact which they illustrate with man’s most dazzling gems, all newly photographed especially for this book.
Obtaining permission to take these photographs and plotting the historical provenance of the gems required a double genius for diplomacy and persistence. It was also the source of a rich yield of anecdotes, retold in the introduction. Almost five years in the preparation, this work is the result of painstaking research, infinite patience, and thousands of miles of air and automobile travel to three continents. The gemstones you see in this book lie closely guarded in museums, private collections, and darkened bank vaults all over the world. Many have never been available for public inspection.
Edita S.A, Lausanne, Switzerland
1974
ISBN 0-517-18132-0
Edita S.A writes:
Through all of the recorded history, jewels have exerted a powerful influence on affairs of men. The Great Book Of Jewels is the first book to capture all the history, romance, intrigue, and enduring beauty of precious stones, from their earliest history to present. The editors, Ernst and Jean Heiniger, aided by a team of nine distinguished gemologists from the world’s foremost museums have amassed a wealth of jewelry lore and scientific fact which they illustrate with man’s most dazzling gems, all newly photographed especially for this book.
Obtaining permission to take these photographs and plotting the historical provenance of the gems required a double genius for diplomacy and persistence. It was also the source of a rich yield of anecdotes, retold in the introduction. Almost five years in the preparation, this work is the result of painstaking research, infinite patience, and thousands of miles of air and automobile travel to three continents. The gemstones you see in this book lie closely guarded in museums, private collections, and darkened bank vaults all over the world. Many have never been available for public inspection.
Synthetic Star Stones
In 1947, the Linde Company began producing synthetic star corundum by the Verneuil (flame fusion) process. Star boules were made by adding 0.1-0.3% of titanium oxide to the mixture. After the boules have cooled, they are reheated to a temperature of 1100-1500ºC for a period of several hours to several days. This causes the titanium oxide to be exsolved in the form of needles arranged in intersecting sets, just like the natural star corundum. The stones, which are known as Linde Stars in the trade are currently produced in several colors, with red and blue being the most common.
For many years they were produced in the United States and often had engraved “L” on the base of the cabochon, which stood for Linde. Today the stones are produced in several other countries as well.
Identification of synthetic star corundum is not a problem because the needles are more evenly distributed and stars appear too good. For now synthetic star is produced by the flame fusion process, and the stones show curved growth lines and gas bubbles characteristic of this process.
For many years they were produced in the United States and often had engraved “L” on the base of the cabochon, which stood for Linde. Today the stones are produced in several other countries as well.
Identification of synthetic star corundum is not a problem because the needles are more evenly distributed and stars appear too good. For now synthetic star is produced by the flame fusion process, and the stones show curved growth lines and gas bubbles characteristic of this process.
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