Konstantin Akinsha writes about Russian faker's incredible talent + experts inability to authenticate genuine paintings despite their years of experience + the skills required to survive as an art dealer in Russia @ http://artnews.com/issues/article.asp?art_id=1975
This reminds me of the 'origin craze' among gemstone collectors, especially Burmese rubies, Kashmir blue sapphires, Colombian emeralds, Golconda diamonds + lately with treated vs. untreated stones. Despite technological advances in gem identification and detection of treatments, famous gem testing laboratories still make spectacular mistakes. Many won't admit it, but that's the truth.
Wednesday, August 01, 2007
The Most Eye-Popping Celebrity Bling
Lea Goldman writes about the most buzzed-about bling in Hollywood + the hip-hop industry's affinity for bling (a term coined in the early '90s by New Orleans rappers the Cash Money Millionaires) + competition among the world's famous jewelers for the red carpet spotlight + other viewpoints @ http://www.forbes.com/2007/07/26/celebrities-bling-hollywood-biz-cz_lg_0726celebbling.html
Further Franchising The Name De Beers And Changing The De Beers LV Business Model
Chaim Even-Zohar writes about De Beers LV business model + sub-sub-sub franchising concept + a new definition for distribution system + other viewpoints @ http://www.idexonline.com/portal_FullEditorial.asp?TextSearch=&KeyMatch=0&id=25636
Composite vs Assembled Opal
Composite opal
These stones are partly made up of opal and partly of the rock which the opal was found in. The rock may be ironstone, quartzite, sandstone or another matrix. This type also includes pseudomorphs in which the opal has replaced another substance. Composite opal consists of a single mass and should not be confused with assembled stones.
Assembled stones normally consist of two parts (doublets) or three parts (triplets) cemented or fused together for providing a better wearing surface; to obtain a large stone from two smaller pieces of natural material; to produce a stone of apparently better color and appearance; for the purpose of supplying a rigid backing or support for fragile materials.
Doublet
Opal doublets consist of a thin slice of precious opal cemented onto a plastic, black onyx, glass or potch (common opal) back. To lower the cost, the top surface is normally flat. Better (and more expensive) doublets are made with thicker pieces of opal, and the surface is domed. Black cement is used to give a dark background for the translucent opal. This gives the appearance of an expensive black opal. Crystal opal makes the best doublets and gray opal the worst. The identification of doublets is not normally difficult, but one must be careful of opal doublets with a potch backing because some solid opals also have a potch backing.
Triplet
As the name implies, opal triplets consist of three parts. The middle section is a thin slice of precious opal, the back is the same as on a doublet, and the top is usually made of rock crystal quartz or another transparent colorless material. This top piece gives the stone greater durability and also magnifies the play of color, thus increasing the beauty. In general, triplets are worth more than doublets. Clear resin is used to cement the quartz top to the opal, and dark resin to cement the opal to the back. Synthetic opal (Gilson) has also been used in place of natural opal for making opal doublets and triplets.
Opal doublets and triplets are easily identified. Unlike other assembled stones, they are not intended to deceive the buyer. They are produced in order to make use or otherwise useless material, and provide the beauty of a fine solid opal at a fraction of the price.
These stones are partly made up of opal and partly of the rock which the opal was found in. The rock may be ironstone, quartzite, sandstone or another matrix. This type also includes pseudomorphs in which the opal has replaced another substance. Composite opal consists of a single mass and should not be confused with assembled stones.
Assembled stones normally consist of two parts (doublets) or three parts (triplets) cemented or fused together for providing a better wearing surface; to obtain a large stone from two smaller pieces of natural material; to produce a stone of apparently better color and appearance; for the purpose of supplying a rigid backing or support for fragile materials.
Doublet
Opal doublets consist of a thin slice of precious opal cemented onto a plastic, black onyx, glass or potch (common opal) back. To lower the cost, the top surface is normally flat. Better (and more expensive) doublets are made with thicker pieces of opal, and the surface is domed. Black cement is used to give a dark background for the translucent opal. This gives the appearance of an expensive black opal. Crystal opal makes the best doublets and gray opal the worst. The identification of doublets is not normally difficult, but one must be careful of opal doublets with a potch backing because some solid opals also have a potch backing.
Triplet
As the name implies, opal triplets consist of three parts. The middle section is a thin slice of precious opal, the back is the same as on a doublet, and the top is usually made of rock crystal quartz or another transparent colorless material. This top piece gives the stone greater durability and also magnifies the play of color, thus increasing the beauty. In general, triplets are worth more than doublets. Clear resin is used to cement the quartz top to the opal, and dark resin to cement the opal to the back. Synthetic opal (Gilson) has also been used in place of natural opal for making opal doublets and triplets.
Opal doublets and triplets are easily identified. Unlike other assembled stones, they are not intended to deceive the buyer. They are produced in order to make use or otherwise useless material, and provide the beauty of a fine solid opal at a fraction of the price.
Phenakite
Chemistry: Beryllium silicate.
Crystal system: Trigonal; short prismatic crystals; seldom large.
Color: Transparent; colorless, light yellow, pink, greenish blue (rare).
Hardness: 7.5
Cleavage: Indistinct: prismatic; fracture: conchoidal.
Specific gravity: 2.95
Refractive index: 1.65 – 1.67; Uniaxial positive; 0.016
Luster: Vitreous.
Dispersion: -
Dichroism: -
Occurrence: Africa, Brazil, Russia.
Notes
From the Greek word meaning to cheat or deceive; confused for quartz; rarely used in jewelry; one of the few crystal inclusions found in synthetic emerald; doubling; faceted.
Crystal system: Trigonal; short prismatic crystals; seldom large.
Color: Transparent; colorless, light yellow, pink, greenish blue (rare).
Hardness: 7.5
Cleavage: Indistinct: prismatic; fracture: conchoidal.
Specific gravity: 2.95
Refractive index: 1.65 – 1.67; Uniaxial positive; 0.016
Luster: Vitreous.
Dispersion: -
Dichroism: -
Occurrence: Africa, Brazil, Russia.
Notes
From the Greek word meaning to cheat or deceive; confused for quartz; rarely used in jewelry; one of the few crystal inclusions found in synthetic emerald; doubling; faceted.
Tuesday, July 31, 2007
Sjunde inseglet, Det (The Seventh Seal)
Memorable quotes from the movie:
Antonius Block (Max von Sydow): I want knowledge! Not faith, not assumptions, but knowledge. I want God to stretch out his hand, uncover his face and speak to me.
Death (Bengt Ekerot): But he remains silent.
Antonius Block (Max von Sydow): I call out to him in the darkness. But it's as if no one was there.
Death (Bengt Ekerot): Perhaps there isn't anyone.
Antonius Block (Max von Sydow): Then life is a preposterous horror. No man can live faced with death, knowing everything's nothingness.
Death (Bengt Ekerot): Most people think neither of death nor nothingness.
Antonius Block (Max von Sydow): But one day you stand at the edge of life and face darkness.
Death (Bengt Ekerot): That day.
Antonius Block (Max von Sydow): I understand what you mean.
Antonius Block (Max von Sydow): I want knowledge! Not faith, not assumptions, but knowledge. I want God to stretch out his hand, uncover his face and speak to me.
Death (Bengt Ekerot): But he remains silent.
Antonius Block (Max von Sydow): I call out to him in the darkness. But it's as if no one was there.
Death (Bengt Ekerot): Perhaps there isn't anyone.
Antonius Block (Max von Sydow): Then life is a preposterous horror. No man can live faced with death, knowing everything's nothingness.
Death (Bengt Ekerot): Most people think neither of death nor nothingness.
Antonius Block (Max von Sydow): But one day you stand at the edge of life and face darkness.
Death (Bengt Ekerot): That day.
Antonius Block (Max von Sydow): I understand what you mean.
Opal Origin
Some experts believe trace element analysis + their ratios by Laser Ablation Inductively Coupled Plasma Mass Spectroscopy (LA-ICP-MS) could pinpoint opal source (s).
No Two Alike
Good Books: (via Emergic) Here is how Publisher's Weekly (via Amazon.com) summarizes the book, No Two Alike:
Why do identical twins who grow up together differ in personality? Harris attempts to solve that mystery. Her initial thesis in The Nurture Assumption: Why Children Turn Out the Way They Do is replaced here with a stronger, more detailed one based on evolutionary psychology. Reading this book is akin to working your way through a mystery novel complete with periodic references to Sherlock Holmes. And Harris has a knack for interspersing scientific and research-laden text with personal anecdotes. Initially, she refutes five red herring theories of personality differences, including differences in environment and gene-environment interactions. Eventually, Harris presents her own theory, starting from modular notions of the brain (as Steven Pinker puts it, "the mind is not a single organ but a system of organs"). Harris offers a three-systems theory of personality: there's the relationship system, the socialization system and the status system. And while she admits her theory of personality isn't simple, it is thought provoking. Harris ties up the loose ends of the new theory, showing how the development of the three systems creates personality.
This is what Scientific American wrote (via Amazon.com):
Where does adult personality come from? Why are we all different? These are the questions energizing Judith Rich Harris's new book. Harris then develops a complex scheme based on "the modular mind," a framework set forth by Harvard University evolutionary psychologist Steven Pinker and others. (Harris herself has no doctorate and is housebound by systemic sclerosis and lupus, two autoimmune disorders.) She describes three modules: the relationship system, the socialization system and the status system, and explains how each contributes its part to making us who we are. The relationship system starts in the cradle as infants study and learn the faces and voices of the people around them, collecting information that helps form personality. The socialization system adapts people to their culture. The status system takes all the information collected during childhood and adolescence and shapes and modifies our personalities in accord with our environments.
Harris's last chapter lays out her theory in tabular form, explaining how each module interacts with the others to produce our distinct personalities. It is lavishly footnoted, like the rest of the book, shoring up her strategy of pointing out the failings of other models and then proposing her own. Her goal, she writes, is to explain the variations in personality that cannot be attributed to variations in people's genes.
It's amazing when you try to understand the link between human nature and individuality + the complex mental infrastructure + the distinguishing characteristics. No Two Alike is a fascinating book because it's a story about us and the people around us.
Why do identical twins who grow up together differ in personality? Harris attempts to solve that mystery. Her initial thesis in The Nurture Assumption: Why Children Turn Out the Way They Do is replaced here with a stronger, more detailed one based on evolutionary psychology. Reading this book is akin to working your way through a mystery novel complete with periodic references to Sherlock Holmes. And Harris has a knack for interspersing scientific and research-laden text with personal anecdotes. Initially, she refutes five red herring theories of personality differences, including differences in environment and gene-environment interactions. Eventually, Harris presents her own theory, starting from modular notions of the brain (as Steven Pinker puts it, "the mind is not a single organ but a system of organs"). Harris offers a three-systems theory of personality: there's the relationship system, the socialization system and the status system. And while she admits her theory of personality isn't simple, it is thought provoking. Harris ties up the loose ends of the new theory, showing how the development of the three systems creates personality.
This is what Scientific American wrote (via Amazon.com):
Where does adult personality come from? Why are we all different? These are the questions energizing Judith Rich Harris's new book. Harris then develops a complex scheme based on "the modular mind," a framework set forth by Harvard University evolutionary psychologist Steven Pinker and others. (Harris herself has no doctorate and is housebound by systemic sclerosis and lupus, two autoimmune disorders.) She describes three modules: the relationship system, the socialization system and the status system, and explains how each contributes its part to making us who we are. The relationship system starts in the cradle as infants study and learn the faces and voices of the people around them, collecting information that helps form personality. The socialization system adapts people to their culture. The status system takes all the information collected during childhood and adolescence and shapes and modifies our personalities in accord with our environments.
Harris's last chapter lays out her theory in tabular form, explaining how each module interacts with the others to produce our distinct personalities. It is lavishly footnoted, like the rest of the book, shoring up her strategy of pointing out the failings of other models and then proposing her own. Her goal, she writes, is to explain the variations in personality that cannot be attributed to variations in people's genes.
It's amazing when you try to understand the link between human nature and individuality + the complex mental infrastructure + the distinguishing characteristics. No Two Alike is a fascinating book because it's a story about us and the people around us.
Fools, Show-offs, And Trophy Hunters
Milton Esterow writes about art thieves in Western Europe + ethnically oriented Balkan bandits + Irish travelers + other viewpoints @ http://artnews.com/issues/article.asp?art_id=1963
Art thieves aren't any different from gem and jewelry thieves. The differences lie in their operating system (s). Gemstones and jewelry are portable, if lucky, easy to liquidate, while paintings require extensive network (s) + the barter culture in certain territories makes it even more complicated.
Art thieves aren't any different from gem and jewelry thieves. The differences lie in their operating system (s). Gemstones and jewelry are portable, if lucky, easy to liquidate, while paintings require extensive network (s) + the barter culture in certain territories makes it even more complicated.
Study Cites Money Laundering By U.S. Diamond Jewelry Retailers
Chaim Even-Zohar writes about Professor John Zdanowicz's views on money laundering (one of America’s top authorities on detecting trade-based money laundering) + analysis and determining abnormal prices + the countries involved + other viewpoints @ http://www.idexonline.com/portal_FullEditorial.asp?TextSearch=&KeyMatch=0&id=25674
Best Bling
Hitha Prabhakar writes about anonymous private individuals searching for the world’s most perfect stones (via diamond suppliers, jewelry houses and auction houses, relying on phone calls and word of mouth) + other viewpoints @ http://www.forbes.com/2007/02/09/rare-expensive-diamonds-forbeslife-cx_hp_0209diamonds.html
Odontolite
Chemistry: Fossilized bones and teeth of pre-historic vertebrates; stained blue by vivianite.
Crystal system: Amorphous; may show features of tooth and bone structure.
Color: Opaque; blue, greenish blue.
Hardness: 5
Cleavage: -
Specific gravity: 3 – 3.15
Refractive index: 1.57 – 1.63 variable
Luster: -
Dispersion: -
Dichroism: -
Occurrence: Miocene sediments of Simorre near Auch, France; also associated with fossilized remains of Siberian mammoths.
Notes
Also known as ‘bone turquoise’; imitated by staining calcined teeth with copper sulphate solution (SG: 1.8; RI:1.54; similar to bone or ivory).
Crystal system: Amorphous; may show features of tooth and bone structure.
Color: Opaque; blue, greenish blue.
Hardness: 5
Cleavage: -
Specific gravity: 3 – 3.15
Refractive index: 1.57 – 1.63 variable
Luster: -
Dispersion: -
Dichroism: -
Occurrence: Miocene sediments of Simorre near Auch, France; also associated with fossilized remains of Siberian mammoths.
Notes
Also known as ‘bone turquoise’; imitated by staining calcined teeth with copper sulphate solution (SG: 1.8; RI:1.54; similar to bone or ivory).
Monday, July 30, 2007
Common Opal
The reason why play-of-color is absent in common opal could be due to:
- variation in sphere size (s).
- non-spherical.
- the spheres may be of identical size (s) but disordered.
- the spheres may be too large or too small to cause diffraction.
- variation in sphere size (s).
- non-spherical.
- the spheres may be of identical size (s) but disordered.
- the spheres may be too large or too small to cause diffraction.
Manga’s Homer And Walt Disney All In One
Malcolm Jones writes about Osamu Tezuka + his action-filled idea-driven graphic novel concepts @ http://www.msnbc.msn.com/id/19996088/site/newsweek/page/0/
Know-How: The 8 Skills That Separate People Who Perform From Those Who Don't.
Good Books: (via Emergic) Here is what Ram Charan’s site says about the book:
How often have you heard someone with a commanding presence deliver a bold vision that turned out to be nothing more than rhetoric and hot air? All too often we mistake the appearance of leadership for the real deal. Without a doubt, intelligence, vision, and the ability to communicate are important. But something big is missing: the know-how of running a business, the capacity to take it in the right direction, do the right things, make the right decisions, deliver results, and leave the people and the business better off than they were before.
For well over four decades, Ram Charan has been learning in the most visceral way the underlying reasons why leaders succeed and fail. As one of the most influential advisors to top management teams of leading companies around the world, he has had a front-row seat to observe the cause and effect of leadership practices and behaviors.
Ram Charan's insight into the real content of leadership provides you with the eight fundamental skills needed for success in the twenty-first century:
- Positioning (and when necessary, repositioning) your business by zeroing in on the central idea that meets customer needs and makes money.
- Connecting the dots by pinpointing patterns of external change ahead of others.
- Shaping the way people work together by leading the social system of your business.
- Judging people by getting to the truth of a person.
- Molding high-energy, high-powered, high-ego people into a working team of leaders in which they equal more than the sum of their parts.
- Knowing the destination where you want to take your business by developing goals that balance what the business can become with what it can realistically achieve.
- Setting laser-sharp priorities that become the road map for meeting your goals.
- Dealing creatively and positively with societal pressures that go beyond the economic value creation activities of your business.
Know-How is the missing link of leadership. By Showing how the eight know-hows link to, interact with, and reinforce personal and psychological traits, Ram Charan provides a holistic and innovative portrait of successful leaders of the twenty-first century.
In my view, it's all about continual change + business models become obselete with time because of the fleeting business landscape + repositioning requires insight, read-through skills, near flawless imagination + the concept of personality traits and know-hows may morph into a new concept + the expanding global economy will bring in more surprises and new models.
How often have you heard someone with a commanding presence deliver a bold vision that turned out to be nothing more than rhetoric and hot air? All too often we mistake the appearance of leadership for the real deal. Without a doubt, intelligence, vision, and the ability to communicate are important. But something big is missing: the know-how of running a business, the capacity to take it in the right direction, do the right things, make the right decisions, deliver results, and leave the people and the business better off than they were before.
For well over four decades, Ram Charan has been learning in the most visceral way the underlying reasons why leaders succeed and fail. As one of the most influential advisors to top management teams of leading companies around the world, he has had a front-row seat to observe the cause and effect of leadership practices and behaviors.
Ram Charan's insight into the real content of leadership provides you with the eight fundamental skills needed for success in the twenty-first century:
- Positioning (and when necessary, repositioning) your business by zeroing in on the central idea that meets customer needs and makes money.
- Connecting the dots by pinpointing patterns of external change ahead of others.
- Shaping the way people work together by leading the social system of your business.
- Judging people by getting to the truth of a person.
- Molding high-energy, high-powered, high-ego people into a working team of leaders in which they equal more than the sum of their parts.
- Knowing the destination where you want to take your business by developing goals that balance what the business can become with what it can realistically achieve.
- Setting laser-sharp priorities that become the road map for meeting your goals.
- Dealing creatively and positively with societal pressures that go beyond the economic value creation activities of your business.
Know-How is the missing link of leadership. By Showing how the eight know-hows link to, interact with, and reinforce personal and psychological traits, Ram Charan provides a holistic and innovative portrait of successful leaders of the twenty-first century.
In my view, it's all about continual change + business models become obselete with time because of the fleeting business landscape + repositioning requires insight, read-through skills, near flawless imagination + the concept of personality traits and know-hows may morph into a new concept + the expanding global economy will bring in more surprises and new models.
Freud Portrait Breaks Art Record
BBC writes about the general trend for contemporary art going up in value @ http://news.bbc.co.uk/2/hi/entertainment/6225168.stm
Did Diamdel Lose The Alexkor Production – Or Just Give It Away?
Chaim Even-Zohar writes about Diamdel South Africa’s dramatic loss of the Alexkor (state-owned) mine/its diamond production + other viewpoints @ http://www.idexonline.com/portal_FullEditorial.asp?TextSearch=&KeyMatch=0&id=25716
India, China To Equal US Jewellery Market
Commodity Online writes about the global gem and jewelry market + the status of India and China by 2015 @ http://www.commodityonline.com/newnews.php?id=1961
King Of Bling
Susan Adams writes about Laurence Graff, the most exclusive diamond merchant, the new Harry Winston, the branding genius + other viewpoints @ http://www.forbes.com/free_forbes/2007/0813/084.html
Meerschaum
(Sepiolite)
Chemistry: Hydrated magnesium silicate
Crystal system: Orthorhombic; microcrystalline; an intermediate mixture of a fine fibrous material and an amorphous substance of the same composition.
Color: Opaque.
Hardness: 2 – 2.5
Cleavage: -
Specific gravity: 2; very porous (when dry it will float in water)
Refractive index: 1.53 mean.
Luster: Earthy
Dispersion: -
Dichroism: -
Occurrence: Alluvial deposits; Greece, Spain, USA, Morocco.
Notes
Soft white and very porous, stains readily (can float); meerschaum from the German word meaning ‘sea foam’; sepiolite from the Greek meaning ‘cuttlefish’; alteration product of serpentine and magnesite; fluorescence: bright blue (long wave); carvings, pipes.
Chemistry: Hydrated magnesium silicate
Crystal system: Orthorhombic; microcrystalline; an intermediate mixture of a fine fibrous material and an amorphous substance of the same composition.
Color: Opaque.
Hardness: 2 – 2.5
Cleavage: -
Specific gravity: 2; very porous (when dry it will float in water)
Refractive index: 1.53 mean.
Luster: Earthy
Dispersion: -
Dichroism: -
Occurrence: Alluvial deposits; Greece, Spain, USA, Morocco.
Notes
Soft white and very porous, stains readily (can float); meerschaum from the German word meaning ‘sea foam’; sepiolite from the Greek meaning ‘cuttlefish’; alteration product of serpentine and magnesite; fluorescence: bright blue (long wave); carvings, pipes.
Sunday, July 29, 2007
Charles Thomas Munger
"It is not given to human beings to have such talent that they can just know everything about everything all the time. But it is given to human beings who work hard at it – who look and sift the world for a mispriced bet – that they can occasionally find one. And the wise ones bet heavily when the world offers them that opportunity. They bet big when they have odds. And the rest of the time, they don't. It's just that simple."
A priceless advice.
A priceless advice.
The Marketing Gurus
Good Books: (via Emergic) The Marketing Gurus by Chris Murray is a collection of summaries of some of the best marketing books. It’s a good concept; one can get a flavor of the best recent ideas in marketing.
Here is a review from Publishers Weekly (via Amazon):
As the editor of Soundview Executive Book Summaries, which distills business books into 5,000-word recaps, Murray offers 17 such summaries of marketing books published in the last 15 years. It's arguably a narrow range for the best "of all time" even with big names like Regis McKenna and Sergio Zyman on board. Each book summary begins with a quick summation, often making redundant the introductions written especially for the collection. And though the condensed versions manage to extract the key ideas from each text, some authors fare better than others. Faith Popcorn's unique voice survives compression, for example, much better than Seth Godin's does. The selected books are sequenced to suggest a broader argument that runs from connecting with customers to marketing in the 21st century, but the actual connections between the various works are largely unstated. Unless you're completely new to marketing research, chances are you've come across at least one of these books already, but Soundview's summaries are a good introduction for those with no background.
This is what the book description says:
Since 1978, Soundview Executive Book Summaries has offered its subscribers condensed versions of the best business books published each year. Soundview’s summaries have won it acclaim as the definitive selection service for sophisticated business book readers.
For the first time ever, Soundview is bringing together summaries of seventeen essential marketing classics in a single volume. The Marketing Gurus distills thousands of pages into fewer than three hundred, making it ideal for busy professionals, students, and anyone curious about how marketing has evolved.
I think it's an excellent introduction for beginners so that they are able to revisit and distill some of the recent marketing ideas.
Here is a review from Publishers Weekly (via Amazon):
As the editor of Soundview Executive Book Summaries, which distills business books into 5,000-word recaps, Murray offers 17 such summaries of marketing books published in the last 15 years. It's arguably a narrow range for the best "of all time" even with big names like Regis McKenna and Sergio Zyman on board. Each book summary begins with a quick summation, often making redundant the introductions written especially for the collection. And though the condensed versions manage to extract the key ideas from each text, some authors fare better than others. Faith Popcorn's unique voice survives compression, for example, much better than Seth Godin's does. The selected books are sequenced to suggest a broader argument that runs from connecting with customers to marketing in the 21st century, but the actual connections between the various works are largely unstated. Unless you're completely new to marketing research, chances are you've come across at least one of these books already, but Soundview's summaries are a good introduction for those with no background.
This is what the book description says:
Since 1978, Soundview Executive Book Summaries has offered its subscribers condensed versions of the best business books published each year. Soundview’s summaries have won it acclaim as the definitive selection service for sophisticated business book readers.
For the first time ever, Soundview is bringing together summaries of seventeen essential marketing classics in a single volume. The Marketing Gurus distills thousands of pages into fewer than three hundred, making it ideal for busy professionals, students, and anyone curious about how marketing has evolved.
I think it's an excellent introduction for beginners so that they are able to revisit and distill some of the recent marketing ideas.
Optical Delusions
Hilarie M. Sheets writes about Tim Eitel's monumental canvases + the psychological tenor of the contemporary-looking figures + other viewpoints @ http://artnews.com/issues/article.asp?art_id=2154
The New Emirate On The Schelde
Chaim Even-Zohar writes about the concept of offshore economies + competition among the key players like Belgium, Dubai, Switzerland, Hong Kong and Israel promising the nomadic tribe of tax exiles with exotic global capital conveniences + other viewpoints @ http://www.idexonline.com/portal_FullEditorial.asp?TextSearch=&KeyMatch=0&id=25748
Lazurite
Chemistry: Isomorphous combination hauynite and sodalite.
Crystal system: Cubic; rarely dodecahedral or compact masses in aggregate.
Color: dark blue or greenish blue
Hardness: 5.5
Cleavage: Imperfect: dodecahedral.
Specific gravity: 2.7 – 2.9
Refractive index: 1.50 mean
Luster: Dull to greasy.
Dispersion: -
Dichroism: -
Occurrence: In limestones as a result of contact metamorphism.
Notes
Lapis lazuli is a complex aggregate of hauynite, sodalite, noselite and lazurite; inclusions: pyrite, calcite.
Crystal system: Cubic; rarely dodecahedral or compact masses in aggregate.
Color: dark blue or greenish blue
Hardness: 5.5
Cleavage: Imperfect: dodecahedral.
Specific gravity: 2.7 – 2.9
Refractive index: 1.50 mean
Luster: Dull to greasy.
Dispersion: -
Dichroism: -
Occurrence: In limestones as a result of contact metamorphism.
Notes
Lapis lazuli is a complex aggregate of hauynite, sodalite, noselite and lazurite; inclusions: pyrite, calcite.
Saturday, July 28, 2007
Billie Holiday
'No two people on earth are alike, it's got to be that way in music or it isn't music.'
In Russia, Red Art Turning To Green
David Holley writes about the new trend (s) in Russia (where the rich are paying top prices for paintings of Socialist realism) + other viewpoints @ http://www.latimes.com/news/nationworld/columnone/la-fg-sovart23apr23,1,6865553.story
The Strategy Paradox
Good Books: (via Emergic) Michael Raynor's The Strategy Paradox via an interview with the author of AlwaysOn.
Here are a few more excerpts from the AlwaysOn interview by Guy Kawasaki:
Question: Why can’t companies predict the future better?
Answer: Companies might be able to predict the future better than they can now, but for me the question is whether they will ever be able to predict the relevant future accurately enough for the purposes of strategic planning, and so avoid, or at least mitigate, the strategy paradox. I don’t think that’s going to happen anytime soon for some deep, structural reasons.
For example, randomness. Prediction requires the identification of a pattern that repeats, because a pattern is what allows you to use what has happened to infer what will happen next. Randomness is the enemy of pattern-based prediction because randomness means that there is no pattern, no way to use the past to predict the future.
Question: What’s the proper role in strategy formation for each level in a hierarchy?
Answer: I’ve found that it helps to think about strategy in two halves: the commitments that all successful strategies entail, and the uncertainties attendant to those commitments. Commitments and uncertainties are only half the answer. The rest of the solution lies in calibrating the focus of each level of the hierarchy to the uncertainties it faces. It is common sense if not common practice that the more senior levels of a hierarchy should be focused on longer time horizons. What hasn’t been as widely recognized is that with longer time horizons come greater levels of uncertainty, and strategic uncertainty in particular. This fact has some profound implications for how each level in an organization should act.
Question: How does your answer change with respect to a start-up?
Answer: Start-ups tend to be enormously resource constrained. Typically they are not able to devote money and time to the problems of strategic uncertainty. As a result, start-ups tend to be bet the farm propositions: high risk, with the potential of high reward. Such firms don’t manage strategic risk, they accept it.
I am in a start-up mode; perhaps, in the coming weeks, months + years ahead I will have more to share so that I am able to see the fruits of my vision, commitment + surprises (as I learn more) + strategies may also teach you something more: the highest probability of extreme success may also bring the highest probability of extreme failure.
Here are a few more excerpts from the AlwaysOn interview by Guy Kawasaki:
Question: Why can’t companies predict the future better?
Answer: Companies might be able to predict the future better than they can now, but for me the question is whether they will ever be able to predict the relevant future accurately enough for the purposes of strategic planning, and so avoid, or at least mitigate, the strategy paradox. I don’t think that’s going to happen anytime soon for some deep, structural reasons.
For example, randomness. Prediction requires the identification of a pattern that repeats, because a pattern is what allows you to use what has happened to infer what will happen next. Randomness is the enemy of pattern-based prediction because randomness means that there is no pattern, no way to use the past to predict the future.
Question: What’s the proper role in strategy formation for each level in a hierarchy?
Answer: I’ve found that it helps to think about strategy in two halves: the commitments that all successful strategies entail, and the uncertainties attendant to those commitments. Commitments and uncertainties are only half the answer. The rest of the solution lies in calibrating the focus of each level of the hierarchy to the uncertainties it faces. It is common sense if not common practice that the more senior levels of a hierarchy should be focused on longer time horizons. What hasn’t been as widely recognized is that with longer time horizons come greater levels of uncertainty, and strategic uncertainty in particular. This fact has some profound implications for how each level in an organization should act.
Question: How does your answer change with respect to a start-up?
Answer: Start-ups tend to be enormously resource constrained. Typically they are not able to devote money and time to the problems of strategic uncertainty. As a result, start-ups tend to be bet the farm propositions: high risk, with the potential of high reward. Such firms don’t manage strategic risk, they accept it.
I am in a start-up mode; perhaps, in the coming weeks, months + years ahead I will have more to share so that I am able to see the fruits of my vision, commitment + surprises (as I learn more) + strategies may also teach you something more: the highest probability of extreme success may also bring the highest probability of extreme failure.
Jonathan Oppenheimer Repeating Great-Grandfather’s Subsidy Demands
Chaim Even-Zohar writes about Jonathan Oppenheimer's views on Botswana's Bushmen + the concept of individual rights + community rights + constitutional rights of the government + government subsidies to cutters + other viewpoints @ http://www.idexonline.com/portal_FullEditorial.asp
Gem Testing
(via The Journal of Gemmology, Vol.10, No.1, January 1966) A E Farn writes:
Recently, a rather rubbed brown cabochon stone in a ring with a reasonable ray to the stone came in for test. At first glance the stone looked a quartz cat’s eye, by the coarse nature of the ray. However, as the stone was worn by bad usage, it could be partially the reason for a poor chrysoberyl looking like quartz. The stone was backed; this prevented one looking at the back of the stone for a hint of quality.
However, the very useful distant vision reading methods of taking a refractive index soon solves the question of quartz or chrysoberyl cat’s eye. Maybe I am going a long way round to bring the point home, but the telephone rang whilst I was looking at the stone in question, and having dealt with that matter I returned to the stone, put a spot of liquid on the refractometer and took a spot reading. I saw quite a reasonable changeover light bar at 1.74 which seemed reasonable enough—completely divorcing it from quartz. Automatically, I turned the spot intensity lamp on and tried to see the chrysoberyl absorption spectrum and could not. I was not surprised; there was a lot of glare from a reflected light (the stone was backed). Something did not seem quite right, so I took the distant vision again and got a good quartz reading.
Then the penny dropped—after answering the telephone I pulled the refractomete towards me and put on methylene iodide as a contact liquid (I have two dropping bottles and two refractometers). The methylene iodide gave a good spot pattern for itself and the quartz being rubbed it did not react as strongly as it should.
There seems to be some sort of moral here about keeping bottles separate, but actually at the moment of writing we are threatened with a telephone strike at night. Well, all I say is, let us have it by the day and get our testing done without interruptions.
Recently, a rather rubbed brown cabochon stone in a ring with a reasonable ray to the stone came in for test. At first glance the stone looked a quartz cat’s eye, by the coarse nature of the ray. However, as the stone was worn by bad usage, it could be partially the reason for a poor chrysoberyl looking like quartz. The stone was backed; this prevented one looking at the back of the stone for a hint of quality.
However, the very useful distant vision reading methods of taking a refractive index soon solves the question of quartz or chrysoberyl cat’s eye. Maybe I am going a long way round to bring the point home, but the telephone rang whilst I was looking at the stone in question, and having dealt with that matter I returned to the stone, put a spot of liquid on the refractometer and took a spot reading. I saw quite a reasonable changeover light bar at 1.74 which seemed reasonable enough—completely divorcing it from quartz. Automatically, I turned the spot intensity lamp on and tried to see the chrysoberyl absorption spectrum and could not. I was not surprised; there was a lot of glare from a reflected light (the stone was backed). Something did not seem quite right, so I took the distant vision again and got a good quartz reading.
Then the penny dropped—after answering the telephone I pulled the refractomete towards me and put on methylene iodide as a contact liquid (I have two dropping bottles and two refractometers). The methylene iodide gave a good spot pattern for itself and the quartz being rubbed it did not react as strongly as it should.
There seems to be some sort of moral here about keeping bottles separate, but actually at the moment of writing we are threatened with a telephone strike at night. Well, all I say is, let us have it by the day and get our testing done without interruptions.
Lazulite
Chemistry: Magnesium aluminum phosphate.
Crystal system: Monoclinic; pointed pyramids; often twinned or granular masses.
Color: Transparent to translucent; medium to dark violetish blue/greenish blue; massive: translucent to opaque, often mottled with white.
Hardness: 5.5
Cleavage: Indistinct: 1 direction; Fracture: brittle, uneven to granular.
Specific gravity: 3.1 – 3.2
Refractive index: 1.62 mean; Biaxial negative; 0.03
Luster: Vitreous.
Dispersion: Low
Dichroism: Strong: colorless to dark blue
Occurrence: Granite pegmatites; Brazil, India, Madagascar, USA, Australia.
Notes
Faceted stones may look like blue apatite; translucent stones may be confused with azurite, lapis lazuli and sodalite; faceted (rare).
Crystal system: Monoclinic; pointed pyramids; often twinned or granular masses.
Color: Transparent to translucent; medium to dark violetish blue/greenish blue; massive: translucent to opaque, often mottled with white.
Hardness: 5.5
Cleavage: Indistinct: 1 direction; Fracture: brittle, uneven to granular.
Specific gravity: 3.1 – 3.2
Refractive index: 1.62 mean; Biaxial negative; 0.03
Luster: Vitreous.
Dispersion: Low
Dichroism: Strong: colorless to dark blue
Occurrence: Granite pegmatites; Brazil, India, Madagascar, USA, Australia.
Notes
Faceted stones may look like blue apatite; translucent stones may be confused with azurite, lapis lazuli and sodalite; faceted (rare).
Friday, July 27, 2007
Sweet Smell Of Success
Memorable quotes from the movie:
J.J. Hunsecker (Burt Lancaster): What's this boy got that Susie likes?
Sidney Falco (Tony Curtis): Integrity - acute, like indigestion.
J.J. Hunsecker (Burt Lancaster): What does that mean - integrity?
Sidney Falco (Tony Curtis): A pocket fulla firecrackers - looking for a match! It's a new wrinkle, to tell the truth... I never thought I'd make a killing on some guy's integrity.
J.J. Hunsecker (Burt Lancaster): What's this boy got that Susie likes?
Sidney Falco (Tony Curtis): Integrity - acute, like indigestion.
J.J. Hunsecker (Burt Lancaster): What does that mean - integrity?
Sidney Falco (Tony Curtis): A pocket fulla firecrackers - looking for a match! It's a new wrinkle, to tell the truth... I never thought I'd make a killing on some guy's integrity.
Robb Report
Robb Report, announced the launch of the Robb Report Global Luxury Index to track the market performance of a representative group of public luxury goods and services companies listed on public exchanges all over the world. More info @ http://www.robbreport.com
An Indian Summer In The United States
Chaim Even-Zohar writes about the changing diamond business landscape in the United States + the special skills required to understand the game + other viewpoints @ http://www.idexonline.com/portal_FullEditorial.asp?TextSearch=&KeyMatch=0&id=25777
Nothing Like This Picasso
Thomas Hoving writes about Pablo Picasso's great 'Les Demoiselles d'Avignon' + the artists interpretation + its special effects on art historians + other viewpoints @ http://www.latimes.com/news/printedition/asection/la-oe-hoving8may08,1,5897482.story
Blue Ocean Strategy
Good Books + New Business Models: (via Emergic) Here is an excerpt from one of the online customer reviews on Amazon.com by Peter Leerskov about the book:
What is a Blue Ocean Strategy?
The authors explain it by comparing it to a red ocean strategy (traditional strategic thinking):
1. Do not compete in existing market space. Instead you should create uncontested market space.
2. Do not beat the competition. Instead you should make the competition irrelevant.
3. Do not exploit existing demand. Instead you should create and capture new demand.
4. Do not make the value/cost trade-off. Instead you should break the value/cost trade-off.
5. Do not align the whole system of a company's activities with its strategic choice of differentiation or low cost. Instead you should align the whole system of a company's activities in pursuit of both differentiation and low cost.
A red ocean strategy is based on traditional strategic thinking - e.g. Harvard's strategy guru Michael Porter. A blue ocean is created in the region where a company's actions favourably affect both its cost structure and it value proposition to buyers. Cost savings are made from eliminating and reducing the factors an industry competes on. Buyer value is lifted by raising and creating elements the industry has never offered. Over time, costs are reduced further as scale economies kick in, due to the high sales volumes that superior value generates.
Examples of strategic moves that created blue oceans of new, untapped demand:
- NetJets (fractional Jet ownership)
- Cirque du Soleil (the circus reinvented for the entertainment market)
- Starbucks (coffee as low-cost luxury for high-end consumers)
- Ebay (online auctioning)
- Sony (the Walkman - personal portable stereos)
- Cars: Japanese fuel-efficient autos (mid-70s) and Chrysler minivan (1984)
- Computers: Apple personal computer (1978) and Dell's built-to-order computers (mid-1990s).
Blue Ocean Strategy provides a framework to start thinking about new opportunities.
I think there must more ideas to come out of Blue Ocean Strategy + the concept is a tipping point + only time will tell whether the concept works in diverse business landscapes.
What is a Blue Ocean Strategy?
The authors explain it by comparing it to a red ocean strategy (traditional strategic thinking):
1. Do not compete in existing market space. Instead you should create uncontested market space.
2. Do not beat the competition. Instead you should make the competition irrelevant.
3. Do not exploit existing demand. Instead you should create and capture new demand.
4. Do not make the value/cost trade-off. Instead you should break the value/cost trade-off.
5. Do not align the whole system of a company's activities with its strategic choice of differentiation or low cost. Instead you should align the whole system of a company's activities in pursuit of both differentiation and low cost.
A red ocean strategy is based on traditional strategic thinking - e.g. Harvard's strategy guru Michael Porter. A blue ocean is created in the region where a company's actions favourably affect both its cost structure and it value proposition to buyers. Cost savings are made from eliminating and reducing the factors an industry competes on. Buyer value is lifted by raising and creating elements the industry has never offered. Over time, costs are reduced further as scale economies kick in, due to the high sales volumes that superior value generates.
Examples of strategic moves that created blue oceans of new, untapped demand:
- NetJets (fractional Jet ownership)
- Cirque du Soleil (the circus reinvented for the entertainment market)
- Starbucks (coffee as low-cost luxury for high-end consumers)
- Ebay (online auctioning)
- Sony (the Walkman - personal portable stereos)
- Cars: Japanese fuel-efficient autos (mid-70s) and Chrysler minivan (1984)
- Computers: Apple personal computer (1978) and Dell's built-to-order computers (mid-1990s).
Blue Ocean Strategy provides a framework to start thinking about new opportunities.
I think there must more ideas to come out of Blue Ocean Strategy + the concept is a tipping point + only time will tell whether the concept works in diverse business landscapes.
Gem Testing
(via The Journal of Gemmology, Vol.10, No.1, January 1966) A E Farn writes:
The stone in question was oval, mixed cut, set in a gold ring—the stone was about 1.75 carats in size. Viewed through the microscope I could see angular zoning of color with a small crescent-shaped feather and on the surface of the stone small zig-zag erupted fractures known as shatter or chatter marks (and doubling of the back facets).
So far as I was concerned, the test was complete. Here was a typical natural blue Ceylon sapphire. My good friend, at home in his own (very efficient) set-up, would have taken the refractive index first. Nothing wrong in doing that, of course, provided you only use your refractometer once or twice a week and there is plenty of time to clean and put it away, etc. But if you test a dozen different pieces of jewelry of all shapes, sizes and categories in a morning between the opening of the registered post and lunch time, you may well forget (we are all human) to wipe off the liquid. You may also (and I have) leave the stone on the refractometer when answering the telephone and later search frantically for a lost stone—to find later, as a result, crystallization of sulphur crystals on the soft glass prism of the refractometer. If in business you suffer no interruptions—you are obviously not doing much business. It is the unavoidable interruptions, the imperious note of the telephone bell (someone wanting to know how much it will cost to test a string of pearls is the usual—and the answer can take time). Even shopkeepers who are busy are guilty of time wasting. Witness the retailer who is offered a pearl necklace to value—he hasn’t a clue but telephones to find out how much it would cost to test.
In the middle of testing a cluster calibré ruby setting to a brooch—the telephone rings, you lose your place and then the customer starts. Usually they have not counted the pearls, they are not conversant with grain size, they did not realize it would possibly have to be cut if genuine, X-rayed if cultured. They cannot give you a lead and are appalled by the charge because they do not realize till then how much is involved. Having courteously dealt with the customer one returns to the brooch and commences again. None of this matters very much provided that along the line of stones inclusions are seen and continuity of testing takes place and you can say that all of the stones you tested are in fact genuine rubies, or synthetic rubies, as the case may be. But how about that one clean stone which gave away nothing? It was a ruby because one saw doubling of the facets and shatter markings—it looked a slightly different red to the others, but because of the nature of the mounting little else other than a vertical sighting in a stone of total diameter under 2mm could be obtained. So here you are and the customer is calling back in a quarter of an hour for the brooch and you have had a lovely time answering the telephone to a probably non-productive caller.
This is not the time for one’s friends to suggest that your methods are not ideal. These occurrences cause certain delays with which our gemological enthusiasts do not have to contend. Gemologists usually deal with loose stones of reasonable size with nice flat facets. Our testing is usually in second-hand jewelry—seldom at its pristine best, with worn facets usually and if the mount is open at the back it is usually clogged up with a fine debris resulting from the onset of talcum powder, cold cream, hand lotion, soap and all the rest of the lotions, potions and detergent deterrents with which the modern woman’s hands are often in contact. I have never had a second-hand piece of jewelry sent in which has been cleaned by the sender for the purpose of testing.
Another béte noir can be the customer who is very important (and knows it) and likes immediate attention, and can hardly bear to wait. I have had such persons who bring in, say, a ruby ring for testing. They are usually very shrewd judges of color and have bought a ring and spent a considerable time testing it in their own office, only to be baffled by perfectly clean stone. What they see tells them it is real but reluctantly they have to have a laboratory test. They then expect some immediate magic in ten seconds—as soon as it is held under the microscope they ask, ‘Is it OK?’ even before one has focused the thing. However, life is not all like that, but most of our customers like to call at least next day for their goods (tested of course).
Having said all this, it now behoves me to settle down to pointing out that despite all the know-how and gadgetry available we cannot always give a definite result while the stone is in a setting. This may seem a little feeble, but in actual fact we seldom ask to have a stone taken from its setting and if we do we usually state our opinion beforehand in order not to appear wise after the event.
Mostly, when we ask for a stone to be taken from a setting, it is a very small synthetic corundum where the curved striae (if any) are running parallel to the girdle and setting. Other difficult cases can be backed baguette colorless stones in a sunken setting precluding refractometer work—these are quite a trial to prove without any doubts lingering.
At one time when we had a colorless cluster surround to a colored center in brooch or ring, we could safely say that the colorless stones were not diamond, and usually the customer was not further interested, since money matters.
Nowadays, we usually get asked what the colorless stones are, and surprisingly quite a large number of colorless/white sapphires in Ceylon jewelry are natural sapphires, which rather goes against the usual run of colorless sapphires, which are usually synthetic.
Quite recently we had a pale-pink stone set in a very ordinary 4-claw gold ring. No shoulder stones—jut a straight-forward native-cut, slightly lumpy, rounded, cushion-shaped stone. At first glance it could be a fancy spinel, a tourmaline or perhaps a pink topaz. Doing the job the wrong way round, according to my learned friend, I looked at the stone through the microscope. Except for doubling of the back facets—a suggestion of a DR of about 0.009—that was all. It could not be topaz, since topaz does not easily or readily show DR. It was not tourmaline, because the birefringence was too small, and it did not quite have the typical color of synthetic or natural pink sapphire. A horrid thought crossed by mind—taafeite. Fortunately for the peace of the laboratory, it did in fact yield a very positive DR for sapphire. My friend, who did not like my method of approach, would have been vindicated by this since he would have put it on a refractometer first of all. Unfortunately, I have a fetish for trying to pin things down by look, color, heft, and then microscope to find DR, inclusions, dichroism, shatter-marks, etc. This pink stone ring set me back a few minutes in probing, but now I had to get started and do the obvious, test for synthetic or genuine. Back to the microscope and a dish of methylene iodide. The stone was very clean; in fact, after quite a lengthy session of turning and turning the stone in ring, lowering the condenser, closing the diaphragm and doing all kinds of useful maneuvers, I cam to a full stop. The stone was a clean pink sapphire with no sign of curves or bubbles, or any feature whatsoever appertaining to natural. After half an hour of concentrated study under ideal conditions, refiltered liquid, cleaned eyepieces, objectives and mirror, I changed my mind several times and then gave it up from a microscope point of view.
One test we often use as a subsidiary is the well known phosphorescence after fluorescence under X-ray of synthetic ruby and pink sapphire. Here, at least, we would get a lead—but no, the stone was completely inert. So it could be genuine. Unfortunately the phosphorescence was only useful to confirm a synthetic whereas the reverse was not so. Our other refinement is to take an immersion contact photograph, hoping, as is so often the case, that structure-lines not readily visible to the naked eye would be revealed by the sensitivity of the film. Once again the result was negative. Somewhat reluctantly we telephoned the customer to ask him to take the stone out.
After the stone was taken out, we found a slight indication of ‘treacle’ and I think, if my memory serves me, a few lines of silk. This was not a stone suitable for the diploma examination. We returned it to our customer finally certified as genuine.
Trouble seldom comes in small doses, for a short while after we had a succession of small insignificant rings with microscopic stones in the center of cluster or as cluster surrounds, and suddenly it seemed as if we were continually asking for stones to be taken out of their settings. However, when one considers we tackle hundreds of items a month of mounted stones, our record is very good.
Gem Testing (continued)
The stone in question was oval, mixed cut, set in a gold ring—the stone was about 1.75 carats in size. Viewed through the microscope I could see angular zoning of color with a small crescent-shaped feather and on the surface of the stone small zig-zag erupted fractures known as shatter or chatter marks (and doubling of the back facets).
So far as I was concerned, the test was complete. Here was a typical natural blue Ceylon sapphire. My good friend, at home in his own (very efficient) set-up, would have taken the refractive index first. Nothing wrong in doing that, of course, provided you only use your refractometer once or twice a week and there is plenty of time to clean and put it away, etc. But if you test a dozen different pieces of jewelry of all shapes, sizes and categories in a morning between the opening of the registered post and lunch time, you may well forget (we are all human) to wipe off the liquid. You may also (and I have) leave the stone on the refractometer when answering the telephone and later search frantically for a lost stone—to find later, as a result, crystallization of sulphur crystals on the soft glass prism of the refractometer. If in business you suffer no interruptions—you are obviously not doing much business. It is the unavoidable interruptions, the imperious note of the telephone bell (someone wanting to know how much it will cost to test a string of pearls is the usual—and the answer can take time). Even shopkeepers who are busy are guilty of time wasting. Witness the retailer who is offered a pearl necklace to value—he hasn’t a clue but telephones to find out how much it would cost to test.
In the middle of testing a cluster calibré ruby setting to a brooch—the telephone rings, you lose your place and then the customer starts. Usually they have not counted the pearls, they are not conversant with grain size, they did not realize it would possibly have to be cut if genuine, X-rayed if cultured. They cannot give you a lead and are appalled by the charge because they do not realize till then how much is involved. Having courteously dealt with the customer one returns to the brooch and commences again. None of this matters very much provided that along the line of stones inclusions are seen and continuity of testing takes place and you can say that all of the stones you tested are in fact genuine rubies, or synthetic rubies, as the case may be. But how about that one clean stone which gave away nothing? It was a ruby because one saw doubling of the facets and shatter markings—it looked a slightly different red to the others, but because of the nature of the mounting little else other than a vertical sighting in a stone of total diameter under 2mm could be obtained. So here you are and the customer is calling back in a quarter of an hour for the brooch and you have had a lovely time answering the telephone to a probably non-productive caller.
This is not the time for one’s friends to suggest that your methods are not ideal. These occurrences cause certain delays with which our gemological enthusiasts do not have to contend. Gemologists usually deal with loose stones of reasonable size with nice flat facets. Our testing is usually in second-hand jewelry—seldom at its pristine best, with worn facets usually and if the mount is open at the back it is usually clogged up with a fine debris resulting from the onset of talcum powder, cold cream, hand lotion, soap and all the rest of the lotions, potions and detergent deterrents with which the modern woman’s hands are often in contact. I have never had a second-hand piece of jewelry sent in which has been cleaned by the sender for the purpose of testing.
Another béte noir can be the customer who is very important (and knows it) and likes immediate attention, and can hardly bear to wait. I have had such persons who bring in, say, a ruby ring for testing. They are usually very shrewd judges of color and have bought a ring and spent a considerable time testing it in their own office, only to be baffled by perfectly clean stone. What they see tells them it is real but reluctantly they have to have a laboratory test. They then expect some immediate magic in ten seconds—as soon as it is held under the microscope they ask, ‘Is it OK?’ even before one has focused the thing. However, life is not all like that, but most of our customers like to call at least next day for their goods (tested of course).
Having said all this, it now behoves me to settle down to pointing out that despite all the know-how and gadgetry available we cannot always give a definite result while the stone is in a setting. This may seem a little feeble, but in actual fact we seldom ask to have a stone taken from its setting and if we do we usually state our opinion beforehand in order not to appear wise after the event.
Mostly, when we ask for a stone to be taken from a setting, it is a very small synthetic corundum where the curved striae (if any) are running parallel to the girdle and setting. Other difficult cases can be backed baguette colorless stones in a sunken setting precluding refractometer work—these are quite a trial to prove without any doubts lingering.
At one time when we had a colorless cluster surround to a colored center in brooch or ring, we could safely say that the colorless stones were not diamond, and usually the customer was not further interested, since money matters.
Nowadays, we usually get asked what the colorless stones are, and surprisingly quite a large number of colorless/white sapphires in Ceylon jewelry are natural sapphires, which rather goes against the usual run of colorless sapphires, which are usually synthetic.
Quite recently we had a pale-pink stone set in a very ordinary 4-claw gold ring. No shoulder stones—jut a straight-forward native-cut, slightly lumpy, rounded, cushion-shaped stone. At first glance it could be a fancy spinel, a tourmaline or perhaps a pink topaz. Doing the job the wrong way round, according to my learned friend, I looked at the stone through the microscope. Except for doubling of the back facets—a suggestion of a DR of about 0.009—that was all. It could not be topaz, since topaz does not easily or readily show DR. It was not tourmaline, because the birefringence was too small, and it did not quite have the typical color of synthetic or natural pink sapphire. A horrid thought crossed by mind—taafeite. Fortunately for the peace of the laboratory, it did in fact yield a very positive DR for sapphire. My friend, who did not like my method of approach, would have been vindicated by this since he would have put it on a refractometer first of all. Unfortunately, I have a fetish for trying to pin things down by look, color, heft, and then microscope to find DR, inclusions, dichroism, shatter-marks, etc. This pink stone ring set me back a few minutes in probing, but now I had to get started and do the obvious, test for synthetic or genuine. Back to the microscope and a dish of methylene iodide. The stone was very clean; in fact, after quite a lengthy session of turning and turning the stone in ring, lowering the condenser, closing the diaphragm and doing all kinds of useful maneuvers, I cam to a full stop. The stone was a clean pink sapphire with no sign of curves or bubbles, or any feature whatsoever appertaining to natural. After half an hour of concentrated study under ideal conditions, refiltered liquid, cleaned eyepieces, objectives and mirror, I changed my mind several times and then gave it up from a microscope point of view.
One test we often use as a subsidiary is the well known phosphorescence after fluorescence under X-ray of synthetic ruby and pink sapphire. Here, at least, we would get a lead—but no, the stone was completely inert. So it could be genuine. Unfortunately the phosphorescence was only useful to confirm a synthetic whereas the reverse was not so. Our other refinement is to take an immersion contact photograph, hoping, as is so often the case, that structure-lines not readily visible to the naked eye would be revealed by the sensitivity of the film. Once again the result was negative. Somewhat reluctantly we telephoned the customer to ask him to take the stone out.
After the stone was taken out, we found a slight indication of ‘treacle’ and I think, if my memory serves me, a few lines of silk. This was not a stone suitable for the diploma examination. We returned it to our customer finally certified as genuine.
Trouble seldom comes in small doses, for a short while after we had a succession of small insignificant rings with microscopic stones in the center of cluster or as cluster surrounds, and suddenly it seemed as if we were continually asking for stones to be taken out of their settings. However, when one considers we tackle hundreds of items a month of mounted stones, our record is very good.
Gem Testing (continued)
Kyanite
(Cyanite) (Disthene)
Chemistry: Aluminum silicate.
Crystal system: Triclinic; long flat bladed prisms; fibrous.
Color: Transparent to translucent; blue, colorless, blue/green.
Hardness: 5 – 7 (directional) 7 across the crystal; 5 along its length.
Cleavage: Perfect: 1 direction, parallel to large prism face; Fracture: brittle, fibrous.
Specific gravity: 3.65 – 3.69
Refractive index: 1.715 – 1.732; Biaxial negative; 0.017
Luster: Vitreous.
Dispersion: Low
Dichroism: Distinct: light blue, colorless, dark blue.
Occurrence: urIn schists and gneisses or granite pegmatites; Burma, India, Brazil, Kenya, USA, Pakistan.
Notes
Polymorph with andalusite and sillimanite (fibrolite); fluorescence: variable; spectral line in deep red and 2 lines in deep blue; faceted.
Chemistry: Aluminum silicate.
Crystal system: Triclinic; long flat bladed prisms; fibrous.
Color: Transparent to translucent; blue, colorless, blue/green.
Hardness: 5 – 7 (directional) 7 across the crystal; 5 along its length.
Cleavage: Perfect: 1 direction, parallel to large prism face; Fracture: brittle, fibrous.
Specific gravity: 3.65 – 3.69
Refractive index: 1.715 – 1.732; Biaxial negative; 0.017
Luster: Vitreous.
Dispersion: Low
Dichroism: Distinct: light blue, colorless, dark blue.
Occurrence: urIn schists and gneisses or granite pegmatites; Burma, India, Brazil, Kenya, USA, Pakistan.
Notes
Polymorph with andalusite and sillimanite (fibrolite); fluorescence: variable; spectral line in deep red and 2 lines in deep blue; faceted.
Nixon
Memorable quotes from the movie:
Richard M. Nixon (Anthony Hopkins): Always remember: others may hate you. But those who hate you don't win unless you hate them. And then you destroy yourself.
Richard M. Nixon (Anthony Hopkins): Always remember: others may hate you. But those who hate you don't win unless you hate them. And then you destroy yourself.
Thursday, July 26, 2007
Breakfast With Gareth Provides Food For Thought
Chaim Even-Zohar shares his views about the remarks made by De Beers Managing Director Gareth Penny at a Gaborone breakfast + the new political and economic diamond map in the region + other viewpoints @ http://www.idexonline.com/portal_FullEditorial.asp?TextSearch=&KeyMatch=0&id=25802
A New Frontier For Chinese Art
Aric Chen writes about Beijing’s lively contemporary art scene + noteworthy spots + other viewpoints @ http://travel.nytimes.com/2007/04/01/travel/01surfacing.html
Casella Wines
New Business Models: (via Emergic) A review in strategy+business
The key element of a blue ocean strategy is a value innovation: a combination of differentiation and low cost that sets a product line or service apart from its competitors. Consider, for example, the story of Yellow Tail, a wine created explicitly for the U.S. market and launched in 2000 by Casella Wines (http://www.casellawine.com.au/), a small, family-owned Australian winery. Casella challenged the wine industry’s givens: that wine is a unique beverage for the informed consumer who requires a complex, wide range of products and is best reached through marketing and brand building that drips with enological terminology.
Casella created a blue ocean by introducing a fun, nontraditional wine targeted at the U.S. drinker who does not normally drink wine, a market three times the size of the U.S. wine market. Soft, sweet, and fruity, Yellow Tail appealed to beer drinkers and ready-to-drink cocktail drinkers, without the traditional focus on tannins, oak, complexity, and aging. Casella made selection easy by offering only one white and one red wine and by replacing the technical jargon with a striking kangaroo logo.
The result: Yellow Tail became the fastest-growing brand in the history of both the U.S. and the Australian wine markets and the No. 1 big-bottle (750ml) red wine in the U.S. by August 2003 and Casella Winery grew to be one of the largest wineries in Australia.
The key element of a blue ocean strategy is a value innovation: a combination of differentiation and low cost that sets a product line or service apart from its competitors. Consider, for example, the story of Yellow Tail, a wine created explicitly for the U.S. market and launched in 2000 by Casella Wines (http://www.casellawine.com.au/), a small, family-owned Australian winery. Casella challenged the wine industry’s givens: that wine is a unique beverage for the informed consumer who requires a complex, wide range of products and is best reached through marketing and brand building that drips with enological terminology.
Casella created a blue ocean by introducing a fun, nontraditional wine targeted at the U.S. drinker who does not normally drink wine, a market three times the size of the U.S. wine market. Soft, sweet, and fruity, Yellow Tail appealed to beer drinkers and ready-to-drink cocktail drinkers, without the traditional focus on tannins, oak, complexity, and aging. Casella made selection easy by offering only one white and one red wine and by replacing the technical jargon with a striking kangaroo logo.
The result: Yellow Tail became the fastest-growing brand in the history of both the U.S. and the Australian wine markets and the No. 1 big-bottle (750ml) red wine in the U.S. by August 2003 and Casella Winery grew to be one of the largest wineries in Australia.
The Man Nobody Knows
Good Books: I have read the book recently; a classic account of Jesus as an entrepreneur, and here is what Richard M Fried has to say about The Man Nobody Knows.
Bruce Barton’s 1925 effort to reconfigure Jesus for the Roaring Twenties turned into one of the great best sellers of the century. In The Man Nobody Knows, Barton depicted Christ as a man’s man, not the meek, effeminate figure he had encountered in Sunday School. No Puritan or Prohibitionist, this Jesus turned water into wine and was “the most popular dinner guest in Jerusalem.” Here was the world’s first advertising man, whose parables sparkled as models for modern jingle writers. (Barton had co-founded the celebrated advertising firm of Batten, Barton, Durstine and Osborn). Here was Christ, the world’s greatest business executive, who “picked up twelve men from the bottom ranks of business and forged them into an organization that conquered the world.”
When in the 1950s Barton felt compelled to revise his often-reprinted book for a new generation, he blurred its focus. In this new edition, the historian Richard Fried revives the primary source in Barton’s original language. In his Introduction, Mr Fried explores the book’s rich insights into the culture of the 1920s, revealing not only the union of religion and business but changing attitudes toward consumption and leisure, sexuality and the roles of men and women.
Bruce Barton’s 1925 effort to reconfigure Jesus for the Roaring Twenties turned into one of the great best sellers of the century. In The Man Nobody Knows, Barton depicted Christ as a man’s man, not the meek, effeminate figure he had encountered in Sunday School. No Puritan or Prohibitionist, this Jesus turned water into wine and was “the most popular dinner guest in Jerusalem.” Here was the world’s first advertising man, whose parables sparkled as models for modern jingle writers. (Barton had co-founded the celebrated advertising firm of Batten, Barton, Durstine and Osborn). Here was Christ, the world’s greatest business executive, who “picked up twelve men from the bottom ranks of business and forged them into an organization that conquered the world.”
When in the 1950s Barton felt compelled to revise his often-reprinted book for a new generation, he blurred its focus. In this new edition, the historian Richard Fried revives the primary source in Barton’s original language. In his Introduction, Mr Fried explores the book’s rich insights into the culture of the 1920s, revealing not only the union of religion and business but changing attitudes toward consumption and leisure, sexuality and the roles of men and women.
Gem Testing
2007: Farn's views on how to run a gem testing lab as a business + working with endlessly complicated clients should provide insights for today's lab gemologists.
(via The Journal of Gemmology, Vol.10, No.1, January 1966) A E Farn writes:
Gem testing could well be the title of a book, a lecture, or merely the sum of all that gemological students imagine is the itinerary of a laboratory gemologist’s day.
Gem testing, generally speaking, is a mixture of items in infinite variety; and if variety is the spice of life—ours is spicy. We are fortunate in having no strictly routine work (in an orderly sense), but because of gemological classes, trade associations and earlier retail experience, we are fortunate in having contact with many aspects of the trade.
Gem testing to the student is usually visualized by stones being tested on the refractometer, or careful wavelength measurement by a spectroscope, crossed-filter work, immersion inspection by microscope, suspension in jars of clerici solution or density work by balance—plus, of course, the mysteries of the endoscope, that unique instrument understood only by a few and capable of use only by the very dextrous, X-rays, fluorescence, phosphorescence, short wave lamps and electro-conductivity tests on rare and pale shades of diamonds. These together with immersion contact photography, Lauegrams and direct radiographs, all join to add to the importance and interest of gem testing.
Strangely enough, a good sense of color, cut and make of stones together with a 10x lens still remain the most useful versatile and flexible adjuncts to the trained gemologists. Gemology, and by that I mean ‘jewelry’ testing, is basically a bread-and-butter science revolving chiefly round the stones which matter: stones such as diamond, emerald, sapphire, ruby, chrysoberyl, peridot, tourmaline, topaz, zircon, quartz, spinel and beryls. These together with opal, pearl, and turquoise, constitute the major importance in the world of gems.
Practically all the money in the gem trade is made by use of these stones in settings of precious metals. The occasional advent of a rare stone in jewelry is interesting to the collectors and non-trade gemologists. Here lies their skill and expertise. Many non-productive hours may be spent in the pursuit of interference figures, refractive indices, indications of positive or negative signs in uniaxial or biaxial stones. Enjoyable as these results may be, they net no cash and cash spells quite a lot of useful things even to gemologists non-trade.
However, fortunately for us, there are still a lot of people who want to know what the center blue stone in a cluster is, or whether the emerald in their Aunt Jane’s pendant is real or not. Probate valuation of deceased person’s jewelry, where the beneficiaries cannot agree as to who have Aunt Maria’s pearls, can be a very useful source of gem testing, for here even the smallest items must be detailed, if only to please the Inland Revenue.
All in all, gem testing, whilst varied, is mundane and concise—very ordinary jewelry set with usually quite small gemstones or pearls of the well-known varieties and, like many other trades or professions, it always seems more interesting to the non-participants. Like watching a plumber wiping a joint—someone else’s job always makes my fingers itch, which brings me to a case in point.
A very good friend of mine, watching with keen interest a test being carried out on a customer’s ring said, ‘You know, you go the wrong way round in your testing. You fly to the most spectacular instead of the more fundamental test in routine matters.’
Here was a challenge flung down on our own doorstep. However good an amateur may be (and he may well be ten times enthusiastic as the professional)—he does testing for love whereas the professional does it for money.
To a professional gemologist, even though he may be a little jaded, the challenge remains constant. He might be right, backed by incontestable facts. To say his facts must be crystal clear (as the gemologists punned it) are the remarks of a gemological pundit.
Gem Testing: ( continued)
(via The Journal of Gemmology, Vol.10, No.1, January 1966) A E Farn writes:
Gem testing could well be the title of a book, a lecture, or merely the sum of all that gemological students imagine is the itinerary of a laboratory gemologist’s day.
Gem testing, generally speaking, is a mixture of items in infinite variety; and if variety is the spice of life—ours is spicy. We are fortunate in having no strictly routine work (in an orderly sense), but because of gemological classes, trade associations and earlier retail experience, we are fortunate in having contact with many aspects of the trade.
Gem testing to the student is usually visualized by stones being tested on the refractometer, or careful wavelength measurement by a spectroscope, crossed-filter work, immersion inspection by microscope, suspension in jars of clerici solution or density work by balance—plus, of course, the mysteries of the endoscope, that unique instrument understood only by a few and capable of use only by the very dextrous, X-rays, fluorescence, phosphorescence, short wave lamps and electro-conductivity tests on rare and pale shades of diamonds. These together with immersion contact photography, Lauegrams and direct radiographs, all join to add to the importance and interest of gem testing.
Strangely enough, a good sense of color, cut and make of stones together with a 10x lens still remain the most useful versatile and flexible adjuncts to the trained gemologists. Gemology, and by that I mean ‘jewelry’ testing, is basically a bread-and-butter science revolving chiefly round the stones which matter: stones such as diamond, emerald, sapphire, ruby, chrysoberyl, peridot, tourmaline, topaz, zircon, quartz, spinel and beryls. These together with opal, pearl, and turquoise, constitute the major importance in the world of gems.
Practically all the money in the gem trade is made by use of these stones in settings of precious metals. The occasional advent of a rare stone in jewelry is interesting to the collectors and non-trade gemologists. Here lies their skill and expertise. Many non-productive hours may be spent in the pursuit of interference figures, refractive indices, indications of positive or negative signs in uniaxial or biaxial stones. Enjoyable as these results may be, they net no cash and cash spells quite a lot of useful things even to gemologists non-trade.
However, fortunately for us, there are still a lot of people who want to know what the center blue stone in a cluster is, or whether the emerald in their Aunt Jane’s pendant is real or not. Probate valuation of deceased person’s jewelry, where the beneficiaries cannot agree as to who have Aunt Maria’s pearls, can be a very useful source of gem testing, for here even the smallest items must be detailed, if only to please the Inland Revenue.
All in all, gem testing, whilst varied, is mundane and concise—very ordinary jewelry set with usually quite small gemstones or pearls of the well-known varieties and, like many other trades or professions, it always seems more interesting to the non-participants. Like watching a plumber wiping a joint—someone else’s job always makes my fingers itch, which brings me to a case in point.
A very good friend of mine, watching with keen interest a test being carried out on a customer’s ring said, ‘You know, you go the wrong way round in your testing. You fly to the most spectacular instead of the more fundamental test in routine matters.’
Here was a challenge flung down on our own doorstep. However good an amateur may be (and he may well be ten times enthusiastic as the professional)—he does testing for love whereas the professional does it for money.
To a professional gemologist, even though he may be a little jaded, the challenge remains constant. He might be right, backed by incontestable facts. To say his facts must be crystal clear (as the gemologists punned it) are the remarks of a gemological pundit.
Gem Testing: ( continued)
Kornerupine
Chemistry: Magnesium aluminum iron boro-silicate.
Crystal system: Orthorhombic; radiating columnar habit; water-worn pebbles.
Color: Transparent to translucent; yellow green, brown, colorless; some chrome-rich green; phenomena: chatoyant (golden eye) and asterated stones.
Hardness: 6.5
Cleavage: Prismatic; Fracture: conchoidal.
Specific gravity: 3.3
Refractive index: 1.67 – 1.68; Biaxial negative; 0.013
Luster: Vitreous.
Dispersion: Low
Dichroism: Brown/green.
Occurrence: Star: Burma; Cat’s eye: Sri Lanka; Green: Madagascar, Tanzania, Kenya.
Notes
Collector’s stone; constants near Enstatite; strong spectral band in the violet and a weak band in the blue 503nm; faceted and cabochon.
Crystal system: Orthorhombic; radiating columnar habit; water-worn pebbles.
Color: Transparent to translucent; yellow green, brown, colorless; some chrome-rich green; phenomena: chatoyant (golden eye) and asterated stones.
Hardness: 6.5
Cleavage: Prismatic; Fracture: conchoidal.
Specific gravity: 3.3
Refractive index: 1.67 – 1.68; Biaxial negative; 0.013
Luster: Vitreous.
Dispersion: Low
Dichroism: Brown/green.
Occurrence: Star: Burma; Cat’s eye: Sri Lanka; Green: Madagascar, Tanzania, Kenya.
Notes
Collector’s stone; constants near Enstatite; strong spectral band in the violet and a weak band in the blue 503nm; faceted and cabochon.
Rembrandt
Memorable quotes from the movie:
Rembrandt van Rijn (Charles Laughton): And of a sudden he knew that when one woman gives herself to you, you possess all women. Women of every age and race and kind, and more than that, the moon, the stars, all miracles and legends are yours. Brown-skinned girls who inflame your senses with their play, cool yellow-haired women who entice and escape you, gentle ones who serve you, slender ones who torment you, the mothers who bore and suckled you; all women whom God created out of the teeming fullness of the earth, are yours in the love of one woman. What is success? A soldier can reckon his success in victories, a merchant in money. But my world is insubstantial. I live in a beautiful, blinding, swirling mist.
Rembrandt van Rijn (Charles Laughton): And of a sudden he knew that when one woman gives herself to you, you possess all women. Women of every age and race and kind, and more than that, the moon, the stars, all miracles and legends are yours. Brown-skinned girls who inflame your senses with their play, cool yellow-haired women who entice and escape you, gentle ones who serve you, slender ones who torment you, the mothers who bore and suckled you; all women whom God created out of the teeming fullness of the earth, are yours in the love of one woman. What is success? A soldier can reckon his success in victories, a merchant in money. But my world is insubstantial. I live in a beautiful, blinding, swirling mist.
Wednesday, July 25, 2007
Art Programs Taking Off At Airports
James Hannah writes about why more and more airports in the United States are using art to boost tourism + improve the image of the community + soothe the passengers + the phenomenon of artport + the effect on the economy + other viewpoints @ http://news.yahoo.com/s/ap_travel/20070723/ap_tr_ge/travel_trend_airport_art
In my view display of gemstone inclusions at the airports + bus terminals across the world should become a new phenomenon in the art world. They are stunning + inspirational + you fall in love with gemstones + the 'natural' inclusions.
In my view display of gemstone inclusions at the airports + bus terminals across the world should become a new phenomenon in the art world. They are stunning + inspirational + you fall in love with gemstones + the 'natural' inclusions.
Blink
Good Books: I have read Blink by Malcolm Gladwell, and here is an excerpt from the book.
Trust your instincts
Don’t think—blink
An art expert sees a ten million dollar sculpture and in a flash realizes it is fake. A fire fighter makes a split-second decision to get out of a blazing building just before it collapses. A marriage analyst studies a fifteen-minute video of a couple and accurately predicts whether they will stay together. A police officer reads a life-or-death situation in the heat of the moment. A speed dater suddenly clicks with the right person…..
Blink is all about those moments when we ‘know’ something without really knowing why, and how this ability is one of the most powerful we possess. A snap judgment made very quickly, Malcolm Gladwell reveals, can actually be far more effective than one made deliberately and cautiously. By blocking out what’s irrelevant and focusing on narrow slices of experience, we can read a seemingly complex situation in the blink of an eye—and discover a radically new way of understanding the world.
This book show us how we can hone our instinctive ability to know in an instant, helping us to bring out the best in our thinking and become better decision makers in our homes, offices and in everyday life. Just as he did with his revolutionary theory of the tipping point, Gladwell reveals how the power of ‘blink’ could fundamentally transform our relationships, the way we consume, create and communicate, how we run our businesses and even our societies.
You will never think about thinking in the same way again.
The concept is not new but the application is. I would very much like the concept applied in the gem and jewelry context + other businesses where 'impulsive buy' is the norm + when you see something you like, you respond. It's spontaneous. Perhaps a unique blink concept? Could be. Anyway it was fun reading the book.
Trust your instincts
Don’t think—blink
An art expert sees a ten million dollar sculpture and in a flash realizes it is fake. A fire fighter makes a split-second decision to get out of a blazing building just before it collapses. A marriage analyst studies a fifteen-minute video of a couple and accurately predicts whether they will stay together. A police officer reads a life-or-death situation in the heat of the moment. A speed dater suddenly clicks with the right person…..
Blink is all about those moments when we ‘know’ something without really knowing why, and how this ability is one of the most powerful we possess. A snap judgment made very quickly, Malcolm Gladwell reveals, can actually be far more effective than one made deliberately and cautiously. By blocking out what’s irrelevant and focusing on narrow slices of experience, we can read a seemingly complex situation in the blink of an eye—and discover a radically new way of understanding the world.
This book show us how we can hone our instinctive ability to know in an instant, helping us to bring out the best in our thinking and become better decision makers in our homes, offices and in everyday life. Just as he did with his revolutionary theory of the tipping point, Gladwell reveals how the power of ‘blink’ could fundamentally transform our relationships, the way we consume, create and communicate, how we run our businesses and even our societies.
You will never think about thinking in the same way again.
The concept is not new but the application is. I would very much like the concept applied in the gem and jewelry context + other businesses where 'impulsive buy' is the norm + when you see something you like, you respond. It's spontaneous. Perhaps a unique blink concept? Could be. Anyway it was fun reading the book.
The Luxury Of Dreams
Chaim Even-Zohar writes about the World Diamond Congress + the impacts of the diamond dream + diamond demand, supply and market structure + other viewpoints @ http://www.idexonline.com/portal_FullEditorial.asp?TextSearch=&KeyMatch=0&id=25842
Cosmetics And Gem Materials
(via The Journal of Gemmology, Vol. IX, No.8, October 1964) R Webster writes:
Chalcedony
The only case of possible attack by cosmetics on chalcedony was one referred to the writer some time ago, and for which, at the time, no decision was reached, particularly as the change seemed so fantastic. Here a lady’s signet ring, set (presumably) with a black onyx, was submitted for investigation. The story which came with the enquiry was that the black stone was originally red (cornelian or stained agate) and had turned black. The owner of the ring was said to be a hairdresser and it was questioned whether chemicals used for hair-treatment could have caused the change of color. No information was given as to the nature of the chemicals used, or the type of hair-dressing preparations used by this hair-dresser. The only question asked was whether such an occurrence had been encountered before. To the best of my knowledge it had not, or at least had not been reported, and the matter rested there.
However, intrigued by the effect which, presumably, had occurred with the stone in the lady’s ring, some experiments were carried out. A piece of cornelian, probably dyed agate, was immersed in a tube of 25% sodium sulphide and left for some time, after which it was removed and dried. No apparent effect was then noticed, but some time later, after the stone had lain on a shelf open to daylight, the stone was seen to have darkened, but admittedly did not turn black but to a very dark brown. The notion underlying this experiment was that as the color of cornelian was due to iron, the action of the sodium sulphide might produce the black ferrous sulphide (FeS).
To perform the second experiment a small piece was broken off from the blackened specimen and immersed in a 20-volume solution of hydrogen peroxide and left for twenty four hours. On the removal of the piece from the solution it was seen that it had returned to the original reddish color, that of cornelian. Another piece was broken off the darkened specimen and immersed in ordinary tap water in order to check whether the darkening was just surface deposit which could be washed off. No lightening took place even after three days immersion. Whether the hydrogen peroxide solution would return the color when other dyes were used is a matter for debate and further experiment.
To get further information the writer approached the technical staff of Golden Ltd, the makers and distributors of the hairdressing products of L’Oreal of Paris, who were good enough to submit specimens of cornelian to treatments with some of their products. These tests involved immersion in samples of Pastel and Progress cold-wave lotions, Ciloreal-skin-stain remover, and a number of basic chemicals used in the manufacturing of L’Oreal products, both for hair coloring and permanent waving. Tests were also carried out by the Golden technicians with a 10% sodium sulphide solution; and one stringent test was with a Pastel cold wave No.1 at a temperature of 75ºC for eight hours. On the return of the stones, in no single instance was any blackening of the stones noticed. Later, however, after the stones had been kept in a stone paper for a few months, two of the pieces did seem to have somewhat darkened in color, but they certainly had not turned black.
It is clear from the above that any change in the color of cornelian could only occur after prolonged treatment, as in the case of the hairdresser who could well be using cosmetic chemicals daily, and would anyway be of rare occurrence, and not an expensive item to replace, but it does illustrate what troubles can be encountered.
The objects of this article is to warn the jeweler that cosmetics, when incorrectly used, may have a deleterious effect on certain types of gem materials. This is no criticism of beauty preparations in themselves when they are used with common sense, but so often ladies are oblivious to the fact that they are wearing their jewelry when completing the final touches to their make-up; then the jeweler is challenged as to the resultant changes.
Chalcedony
The only case of possible attack by cosmetics on chalcedony was one referred to the writer some time ago, and for which, at the time, no decision was reached, particularly as the change seemed so fantastic. Here a lady’s signet ring, set (presumably) with a black onyx, was submitted for investigation. The story which came with the enquiry was that the black stone was originally red (cornelian or stained agate) and had turned black. The owner of the ring was said to be a hairdresser and it was questioned whether chemicals used for hair-treatment could have caused the change of color. No information was given as to the nature of the chemicals used, or the type of hair-dressing preparations used by this hair-dresser. The only question asked was whether such an occurrence had been encountered before. To the best of my knowledge it had not, or at least had not been reported, and the matter rested there.
However, intrigued by the effect which, presumably, had occurred with the stone in the lady’s ring, some experiments were carried out. A piece of cornelian, probably dyed agate, was immersed in a tube of 25% sodium sulphide and left for some time, after which it was removed and dried. No apparent effect was then noticed, but some time later, after the stone had lain on a shelf open to daylight, the stone was seen to have darkened, but admittedly did not turn black but to a very dark brown. The notion underlying this experiment was that as the color of cornelian was due to iron, the action of the sodium sulphide might produce the black ferrous sulphide (FeS).
To perform the second experiment a small piece was broken off from the blackened specimen and immersed in a 20-volume solution of hydrogen peroxide and left for twenty four hours. On the removal of the piece from the solution it was seen that it had returned to the original reddish color, that of cornelian. Another piece was broken off the darkened specimen and immersed in ordinary tap water in order to check whether the darkening was just surface deposit which could be washed off. No lightening took place even after three days immersion. Whether the hydrogen peroxide solution would return the color when other dyes were used is a matter for debate and further experiment.
To get further information the writer approached the technical staff of Golden Ltd, the makers and distributors of the hairdressing products of L’Oreal of Paris, who were good enough to submit specimens of cornelian to treatments with some of their products. These tests involved immersion in samples of Pastel and Progress cold-wave lotions, Ciloreal-skin-stain remover, and a number of basic chemicals used in the manufacturing of L’Oreal products, both for hair coloring and permanent waving. Tests were also carried out by the Golden technicians with a 10% sodium sulphide solution; and one stringent test was with a Pastel cold wave No.1 at a temperature of 75ºC for eight hours. On the return of the stones, in no single instance was any blackening of the stones noticed. Later, however, after the stones had been kept in a stone paper for a few months, two of the pieces did seem to have somewhat darkened in color, but they certainly had not turned black.
It is clear from the above that any change in the color of cornelian could only occur after prolonged treatment, as in the case of the hairdresser who could well be using cosmetic chemicals daily, and would anyway be of rare occurrence, and not an expensive item to replace, but it does illustrate what troubles can be encountered.
The objects of this article is to warn the jeweler that cosmetics, when incorrectly used, may have a deleterious effect on certain types of gem materials. This is no criticism of beauty preparations in themselves when they are used with common sense, but so often ladies are oblivious to the fact that they are wearing their jewelry when completing the final touches to their make-up; then the jeweler is challenged as to the resultant changes.
Idocrase (Vesuvianite)
Chemistry: Calcium aluminum silicate.
Crystal system: Tetragonal; Vesuvianite: well-developed square prisms capped with bipyramidal and often basal pinacoid; Californite: massive; Cyprine: massive.
Color: Vesuvianite: transparent, yellow to brown and greenish shades; Californite: transparent to opaque; massive green (mixture of idocrase and grossular garnet); Cyprine: very rare blue variety (Cu).
Hardness: 6 - 7
Cleavage: Indistinct; Fracture: sub-conchoidal.
Specific gravity: 3.35
Refractive index: 1.70 – 1.73 (changes from negative to positive with increasing R.I); 0.005
Luster: Vitreous.
Dispersion: Low
Dichroism: Indistinct.
Occurrence: Canada, Italy, Switzerland, Siberia; Californite: California, USA.
Notes
Vesuvianite cut for collectors; crystals similar to zircon, except zircon rarely shows the basal pinacoid; massive green Californite may look like nephrite jade; massive idocrase often mixed with hydrogrossular; may show rare earth spectrum, strong band at 461nm in the blue; transparent varieties faceted; Californite: cabochon and beads.
Crystal system: Tetragonal; Vesuvianite: well-developed square prisms capped with bipyramidal and often basal pinacoid; Californite: massive; Cyprine: massive.
Color: Vesuvianite: transparent, yellow to brown and greenish shades; Californite: transparent to opaque; massive green (mixture of idocrase and grossular garnet); Cyprine: very rare blue variety (Cu).
Hardness: 6 - 7
Cleavage: Indistinct; Fracture: sub-conchoidal.
Specific gravity: 3.35
Refractive index: 1.70 – 1.73 (changes from negative to positive with increasing R.I); 0.005
Luster: Vitreous.
Dispersion: Low
Dichroism: Indistinct.
Occurrence: Canada, Italy, Switzerland, Siberia; Californite: California, USA.
Notes
Vesuvianite cut for collectors; crystals similar to zircon, except zircon rarely shows the basal pinacoid; massive green Californite may look like nephrite jade; massive idocrase often mixed with hydrogrossular; may show rare earth spectrum, strong band at 461nm in the blue; transparent varieties faceted; Californite: cabochon and beads.
Cirque du Soleil
New Business Model: An excellent insight + a new definition for competition.
(via emergic) An excerpt from the book, Blue Ocean Strategy, in Fast Company:
A one time accordion player, stilt-walker and fire-eater, Guy Laliberte is now CEO of one of Canada's largest cultural exports, Cirque du Soleil (http://www.cirquedusoleil.com). Created in 1984 by a group of street performers, Cirque's productions have been seen by almost 40 million people in 90 cities around the world. In less than 20 years Cirque du Soleil has achieved a revenue level that took Ringling Brothers and Barnum & Bailey's Circus - the global champion of the circus industry - more than one hundred years to attain.
What makes this all the more remarkable is that this rapid growth was not achieved in an attractive industry. It was in a declining industry in which traditional strategic analysis pointed to limited potential for growth. Supplier power on the part of star performers was strong. So was buyer power? From the perspective of competition-based strategy, then, the circus industry appeared unattractive.
Another compelling aspect of Cirque du Soleil's success is that it did not win by taking customers from the already shrinking demand for the circus industry, which historically catered to children. Cirque du Soleil did not compete with Ringling Brothers and Barnum & Bailey's Circus to make this happen. Instead it created uncontested new market space that made the competition irrelevant. It appealed to a whole new group of customers - adults and corporate clients prepared to pay a price that is several times as expensive as traditional circuses for their unprecedented entertainment experience. Significantly, one of the first Cirque productions was titled "We Reinvent the Circus".
Cirque du Soleil succeeded because it realized that to win in the future, companies must stop competing with each other. The only way to beat the competition is to stop trying to beat the competition.
In a brief article in Fast Company, Renee Mauborgne, the co-author of Blue Ocean Strategy, says companies can do what Cirque du Soleil did by following certain guidelines.
- Water, water, everywhere.
- You don't have to compete in a red ocean of bloody competition. Even exhausted industries -- like the circus can be reinvented.
- Don't swim with the school.
- Quit benchmarking the competition or setting your strategic agenda in the context of theirs.
- Find new ponds to fish.
- Don't assume your current customers have the insights you need to rethink your strategy. Look to non-customers instead.
- Cut bait on costs.
- Put as much emphasis on what you can eliminate as on what you can create.
(via emergic) An excerpt from the book, Blue Ocean Strategy, in Fast Company:
A one time accordion player, stilt-walker and fire-eater, Guy Laliberte is now CEO of one of Canada's largest cultural exports, Cirque du Soleil (http://www.cirquedusoleil.com). Created in 1984 by a group of street performers, Cirque's productions have been seen by almost 40 million people in 90 cities around the world. In less than 20 years Cirque du Soleil has achieved a revenue level that took Ringling Brothers and Barnum & Bailey's Circus - the global champion of the circus industry - more than one hundred years to attain.
What makes this all the more remarkable is that this rapid growth was not achieved in an attractive industry. It was in a declining industry in which traditional strategic analysis pointed to limited potential for growth. Supplier power on the part of star performers was strong. So was buyer power? From the perspective of competition-based strategy, then, the circus industry appeared unattractive.
Another compelling aspect of Cirque du Soleil's success is that it did not win by taking customers from the already shrinking demand for the circus industry, which historically catered to children. Cirque du Soleil did not compete with Ringling Brothers and Barnum & Bailey's Circus to make this happen. Instead it created uncontested new market space that made the competition irrelevant. It appealed to a whole new group of customers - adults and corporate clients prepared to pay a price that is several times as expensive as traditional circuses for their unprecedented entertainment experience. Significantly, one of the first Cirque productions was titled "We Reinvent the Circus".
Cirque du Soleil succeeded because it realized that to win in the future, companies must stop competing with each other. The only way to beat the competition is to stop trying to beat the competition.
In a brief article in Fast Company, Renee Mauborgne, the co-author of Blue Ocean Strategy, says companies can do what Cirque du Soleil did by following certain guidelines.
- Water, water, everywhere.
- You don't have to compete in a red ocean of bloody competition. Even exhausted industries -- like the circus can be reinvented.
- Don't swim with the school.
- Quit benchmarking the competition or setting your strategic agenda in the context of theirs.
- Find new ponds to fish.
- Don't assume your current customers have the insights you need to rethink your strategy. Look to non-customers instead.
- Cut bait on costs.
- Put as much emphasis on what you can eliminate as on what you can create.
Tuesday, July 24, 2007
The Private Life Of Henry VIII.
Memorable quote (s) from the movie:
King Henry VIII (Charles Laughton): Diplomacy? Diplomacy, my foot! I'm an Englishman -- I can't say one thing and mean another. What I can do is to build ships, ships, and then more ships!
Thomas Cromwell (Franklin Dyall): You mean, double the fleet?
King Henry VIII (Charles Laughton): Treble it. Fortify Dover. Rule the sea.
Thomas Cromwell (Charles Laughton): To do this will cost us money, sire.
King Henry VIII (Charles Laughton): To leave it undone will cost us England.
King Henry VIII (Charles Laughton): Diplomacy? Diplomacy, my foot! I'm an Englishman -- I can't say one thing and mean another. What I can do is to build ships, ships, and then more ships!
Thomas Cromwell (Franklin Dyall): You mean, double the fleet?
King Henry VIII (Charles Laughton): Treble it. Fortify Dover. Rule the sea.
Thomas Cromwell (Charles Laughton): To do this will cost us money, sire.
King Henry VIII (Charles Laughton): To leave it undone will cost us England.
Biopics Mix Shticks, Kitsch
Peter Plagens writes about movie makers love to dramatise the lives of famous artists + the boom in sub-genre (s) + other viewpoints @ http://artnews.com/issues/article.asp?art_id=2167
A Singapore Jeweler’s Nightmare Scenario
Chaim Even-Zohar writes about David Rasif & Partners, a law firm in Singapore, the police, the diamond market + other viewpoints @ http://www.idexonline.com/portal_FullEditorial.aspTextSearch=&KeyMatch=0&id=25869
Cosmetics And Gem Materials
(via The Journal of Gemmology, Vol. IX, No.8, October 1964) R Webster writes:
Turquoise and jade
Most turquoise has been treated in some way to improve the color and substances used for this treatment may be affected when cosmetic preparations get on to the surface of the stone. Even good colored non-treated turquoise may be affected by certain cosmetics. Robert Crowningshield refers to a case in which turquoise had discolored, apparently from the effects of cosmetics. There has been no report that jades have been affected by beauty preparations, but as jadeite can be dyed, deleterious effects could conceivably occur with this material.
Cosmetics And Gem Materials (continued)
Turquoise and jade
Most turquoise has been treated in some way to improve the color and substances used for this treatment may be affected when cosmetic preparations get on to the surface of the stone. Even good colored non-treated turquoise may be affected by certain cosmetics. Robert Crowningshield refers to a case in which turquoise had discolored, apparently from the effects of cosmetics. There has been no report that jades have been affected by beauty preparations, but as jadeite can be dyed, deleterious effects could conceivably occur with this material.
Cosmetics And Gem Materials (continued)
Hypersthene
Chemistry: Form of Enstatite, with increased iron content, usually opaque.
Crystal system: Orthorhombic; rarely short prismatic crystals; lamellar masses common.
Color: Opaque; gem varieties dark brown with coppery iridescence; hypersthene enstatite: transparent brown.
Hardness: 5 - 6
Cleavage: Good: in 1 direction.
Specific gravity: 3.4 – 3.5
Refractive index: 1.6 – 1.79; 1.673 – 1.731; Biaxial negative (optic sign changes along the series); 0.014
Luster: Vitreous, pearly or silky.
Dispersion: Low
Dichroism: Pinkish to greenish.
Occurrence: Igneous and metamorphic, also from meteorites; Norway, Greenland, Germany, USA, Mexico.
Notes
Also called ferrohypersthene; varieties include bronzite; spectral line at 506nm and 547nm; cabochon, slab.
Crystal system: Orthorhombic; rarely short prismatic crystals; lamellar masses common.
Color: Opaque; gem varieties dark brown with coppery iridescence; hypersthene enstatite: transparent brown.
Hardness: 5 - 6
Cleavage: Good: in 1 direction.
Specific gravity: 3.4 – 3.5
Refractive index: 1.6 – 1.79; 1.673 – 1.731; Biaxial negative (optic sign changes along the series); 0.014
Luster: Vitreous, pearly or silky.
Dispersion: Low
Dichroism: Pinkish to greenish.
Occurrence: Igneous and metamorphic, also from meteorites; Norway, Greenland, Germany, USA, Mexico.
Notes
Also called ferrohypersthene; varieties include bronzite; spectral line at 506nm and 547nm; cabochon, slab.
Monday, July 23, 2007
Is FinCEN’s AML/CFT Jewelry Rule Non-Compliant With International Standards?
Chaim Even-Zohar writes about the lack of harmonization of anti-money laundering rules among the key players + various interpretations by the government, diamond and jewelry sector + other viewpoints @ http://www.idexonline.com/portal_FullEditorial.asp?TextSearch=&KeyMatch=0&id=25907
Botswana Govt 'Own Worst Enemy' In dealing With San Issue
Martin Creamer writes about relocation of the Koisan, the bushmen + De Beer's commitment for near-mine communities + the economic position of the government + other viewpoints @ http://www.miningweekly.co.za/article.php?a_id=112985
Why Diamonds Are For The Long-term
(via Moneyweek) Garry White writes @ ‘Garry Writes’, his views on specific recommendations in the resource, infrastructure and biotech sectors via Outstanding Investments
Cosmetics And Gem Materials
2007: I stumbled upon this article during my research. It's an excellent article on cosmetics and the after-effects on pearls and other gem materials.
(via The Journal of Gemmology, Vol. IX, No.8, October 1964) R Webster writes:
Little has been recorded in literature of the possible effects on certain types of gem materials and pearls by the action of cosmetics used in beauty treatments, despite the fact that the embellishment of the natural appearance of women, and men, by the application of various preparations of mineral, animal and vegetable nature have been used since prehistoric times. The extensive use of the modern artificially made products used in beauty treatments today makes consideration of their effects of some importance.
It is quite clear that no harm will come to those gemstones cut from single crystals, except the greasy components of some cosmetics may adhere to the setting and backs of the stones causing them to lose their brilliancy. This, of course, is most important with diamond, a stone which collects grease so readily, and whose optical properties depend so much on the total internal reflection of light from the rear facets. Periodical cleaning is the answer here, and as this should be done anyway, there is no problem.
Those gem materials which are to some extent porous (and, indeed, these are the gems which can be artificially colored by stain or dye) are obviously those most likely to be adversely affected by the haphazard use of various cosmetic preparations. The most important of such gems are pearl, turquoise, opal and jade, and possibly agate and coral. Pearls are the most likely to suffer damage owing to the nature of their structure and to the fact that in the case of necklets especially, and to some extent earrings, they, when worn lie close to the skin or hair.
When it is realized that cosmetic preparations cover such fields as hair dyes and bleaches, depilatories, skin creams and face powders, hair-setting lotions and sprays, as well as eye shadow, lipstick and nail varnishes, and that each manufacturer has a different formula for his various products, it is obvious that any complete investigation would need the full time services of several workers. This, from economic considerations alone, would be out of the question. Some experiments and some actual cases which have been investigated and which have been reported from other workers are here recorded.
Pearls
Experience has shown that there are two distinct ways in which cosmetics can affect pearls. These are surface contamination and contamination which has worked inwardly through the string canal.
Surface contamination mostly occurs through the use of hair-setting sprays, perspiration deodorant sprays, and atomized perfumes. Hair-setting sprays often contain a synthetic cellulose derivative, such as methyl cellulose, and this, if used when pearls are worn, may give a coating of lacquer to them. Such an accidental lacquering, as has been shown by experiment, so coats the pearls that a pin drawn across the surface will dig up this coating in a similar manner to the effect shown when a pin is pressed against a solid glass type imitation pearl. Further, this coating tends to mask the suture marks, that is the overlapping edges of the aragonite platelets, and this also tends to give the impression that one is dealing with an imitation pearl.
When this extraneous coating ages, or has collected on the pearls rather as droplets than as a complete covering, the coating may peel or flake off and give the impression that it is the pearls that are flaking away. It is well for the jeweler to be mindful of this, as it has not been unknown for a customer to complain of this flaking of her pearls.
The second type of contamination, inwardly, may be illustrated by an actual case where an investigation was carried out. Briefly, a cultured pearl necklet was restrung by a jeweler on behalf of a customer and after about three months had elapsed the lady brought the necklet back and complained that since the pearls had been restrung a number of pearls had turned to a blackish color. The jeweler’s assistant who saw the lady fully agreed that some of the pearls had blackened and asked her to call again and discuss the matter with the manager. Instead of so doing the lady took the necklet to another jeweler, who had previously valued the necklet for insurance purposes. As would be expected the value now placed upon the necklet was considerably less than before, whereupon the indignant lady took the pearls to the local police station and lodged a complaint against the first jeweler.
The police interviewed the jeweler and suggested that a laboratory investigation should be made. The necklet, now in pieces, for the police had cut from the necklet all the blackened pearls, came into the hands of the writer for an investigation as to the cause of the blackening of the pearls. From previous experiments it was known that some pearls appear to darken by possible sulphiding of a metallic compound, which may have adventitiously been taken up by the organic part of the pearl, or by dirty grease entering the pearl through the stringing canal. There is a further, but unlikely, contingency that silver nitrate, which is used in some hair dyes, might be the activating factor, just as it is used for dyeing pearls black.
Examination of the string of the necklet under investigation showed some grease to be present, and that the snap itself was covered by grease, and to such an extent that one of the diamonds set in it was completely covered and could not be seen. Grease was evidently the answer here, but for completeness of the investigation a test for sulphiding was carried out. This gave a negative result.
Some of the discolored pearls were then degreased by using a Soxhlet extraction apparatus. After this treatment the pearls were found to be much whiter, and grease was recovered from the solvent used for the degreasing.
What happened here was that grease, presumably from cosmetic creams, had entered, by capillary attraction, along the stringing canal and up and around the discontinuation layer between the bead nucleus and the outer nacreous layer. The grease had darkened, owning to ageing and admixture with dirt, and this showed through the translucent pearly outside layer and make the pearls appear dark colored.
(continued)
(via The Journal of Gemmology, Vol. IX, No.8, October 1964) R Webster writes:
Little has been recorded in literature of the possible effects on certain types of gem materials and pearls by the action of cosmetics used in beauty treatments, despite the fact that the embellishment of the natural appearance of women, and men, by the application of various preparations of mineral, animal and vegetable nature have been used since prehistoric times. The extensive use of the modern artificially made products used in beauty treatments today makes consideration of their effects of some importance.
It is quite clear that no harm will come to those gemstones cut from single crystals, except the greasy components of some cosmetics may adhere to the setting and backs of the stones causing them to lose their brilliancy. This, of course, is most important with diamond, a stone which collects grease so readily, and whose optical properties depend so much on the total internal reflection of light from the rear facets. Periodical cleaning is the answer here, and as this should be done anyway, there is no problem.
Those gem materials which are to some extent porous (and, indeed, these are the gems which can be artificially colored by stain or dye) are obviously those most likely to be adversely affected by the haphazard use of various cosmetic preparations. The most important of such gems are pearl, turquoise, opal and jade, and possibly agate and coral. Pearls are the most likely to suffer damage owing to the nature of their structure and to the fact that in the case of necklets especially, and to some extent earrings, they, when worn lie close to the skin or hair.
When it is realized that cosmetic preparations cover such fields as hair dyes and bleaches, depilatories, skin creams and face powders, hair-setting lotions and sprays, as well as eye shadow, lipstick and nail varnishes, and that each manufacturer has a different formula for his various products, it is obvious that any complete investigation would need the full time services of several workers. This, from economic considerations alone, would be out of the question. Some experiments and some actual cases which have been investigated and which have been reported from other workers are here recorded.
Pearls
Experience has shown that there are two distinct ways in which cosmetics can affect pearls. These are surface contamination and contamination which has worked inwardly through the string canal.
Surface contamination mostly occurs through the use of hair-setting sprays, perspiration deodorant sprays, and atomized perfumes. Hair-setting sprays often contain a synthetic cellulose derivative, such as methyl cellulose, and this, if used when pearls are worn, may give a coating of lacquer to them. Such an accidental lacquering, as has been shown by experiment, so coats the pearls that a pin drawn across the surface will dig up this coating in a similar manner to the effect shown when a pin is pressed against a solid glass type imitation pearl. Further, this coating tends to mask the suture marks, that is the overlapping edges of the aragonite platelets, and this also tends to give the impression that one is dealing with an imitation pearl.
When this extraneous coating ages, or has collected on the pearls rather as droplets than as a complete covering, the coating may peel or flake off and give the impression that it is the pearls that are flaking away. It is well for the jeweler to be mindful of this, as it has not been unknown for a customer to complain of this flaking of her pearls.
The second type of contamination, inwardly, may be illustrated by an actual case where an investigation was carried out. Briefly, a cultured pearl necklet was restrung by a jeweler on behalf of a customer and after about three months had elapsed the lady brought the necklet back and complained that since the pearls had been restrung a number of pearls had turned to a blackish color. The jeweler’s assistant who saw the lady fully agreed that some of the pearls had blackened and asked her to call again and discuss the matter with the manager. Instead of so doing the lady took the necklet to another jeweler, who had previously valued the necklet for insurance purposes. As would be expected the value now placed upon the necklet was considerably less than before, whereupon the indignant lady took the pearls to the local police station and lodged a complaint against the first jeweler.
The police interviewed the jeweler and suggested that a laboratory investigation should be made. The necklet, now in pieces, for the police had cut from the necklet all the blackened pearls, came into the hands of the writer for an investigation as to the cause of the blackening of the pearls. From previous experiments it was known that some pearls appear to darken by possible sulphiding of a metallic compound, which may have adventitiously been taken up by the organic part of the pearl, or by dirty grease entering the pearl through the stringing canal. There is a further, but unlikely, contingency that silver nitrate, which is used in some hair dyes, might be the activating factor, just as it is used for dyeing pearls black.
Examination of the string of the necklet under investigation showed some grease to be present, and that the snap itself was covered by grease, and to such an extent that one of the diamonds set in it was completely covered and could not be seen. Grease was evidently the answer here, but for completeness of the investigation a test for sulphiding was carried out. This gave a negative result.
Some of the discolored pearls were then degreased by using a Soxhlet extraction apparatus. After this treatment the pearls were found to be much whiter, and grease was recovered from the solvent used for the degreasing.
What happened here was that grease, presumably from cosmetic creams, had entered, by capillary attraction, along the stringing canal and up and around the discontinuation layer between the bead nucleus and the outer nacreous layer. The grease had darkened, owning to ageing and admixture with dirt, and this showed through the translucent pearly outside layer and make the pearls appear dark colored.
(continued)
Howlite
Chemistry: Silico-borate of calcium.
Crystal system: Monoclinic; massive; compact nodules.
Color: Semi translucent to opaque; white material veined with dark gray or black.
Hardness: 3.5
Cleavage: -
Specific gravity: 2.52 (2.52 – 2.57)
Refractive index: 1.53 mean; aggregate.
Luster: Vitreous to sub-vitreous.
Dispersion: -
Dichroism: -
Occurrence: USA
Notes
Ornamental material; frequently dyed blue (turquoise, lapis); less often other colors (coral, jade); identification based on magnification, appearance (texture, color, structural markings); look for dye concentrations in cracks and grain boundaries; color, may be unstable; fluorescence: brownish yellow (short wave); some Californian material may fluoresce orange (long wave); cabochon, beads, carvings.
Crystal system: Monoclinic; massive; compact nodules.
Color: Semi translucent to opaque; white material veined with dark gray or black.
Hardness: 3.5
Cleavage: -
Specific gravity: 2.52 (2.52 – 2.57)
Refractive index: 1.53 mean; aggregate.
Luster: Vitreous to sub-vitreous.
Dispersion: -
Dichroism: -
Occurrence: USA
Notes
Ornamental material; frequently dyed blue (turquoise, lapis); less often other colors (coral, jade); identification based on magnification, appearance (texture, color, structural markings); look for dye concentrations in cracks and grain boundaries; color, may be unstable; fluorescence: brownish yellow (short wave); some Californian material may fluoresce orange (long wave); cabochon, beads, carvings.
Coffee Grading vs Colored Stone Grading
(via Coffee Review) Retailers may also qualify coffee labels by grade name. Grading is a device for controlling the quality of an agricultural commodity so that buyer and seller can do business without personally examining every lot sold. Coffee grading terminology is, unfortunately, varied and obscure. Every coffee-growing country has its own set of terms, and few are distinguished by logical clarity. Kenya AA is an exception: Clearly AA is better than A or B. But though the Colombian terms excelso and supremo are both laudatory, one could hardly determine by reason alone that supremo is the highest grade of Colombian coffee, and excelso a more comprehensive grade consisting of a mixture of supremo and the less desirable extra grade. Although we may be aware that altitude is a prime grading factor in Central American coffees, one could hardly guess without coaching that strictly hard bean refers to Guatemalan coffees grown at altitudes of 4,500 to 5,000 feet, and hard bean to those at 4,000 to 4,500 feet. The higher the altitude, the slower-maturing the bean, and the harder and denser its substance--hence hard bean.
Comparing colored stones with coffee: There are similarities. There are no internationally accepted systematic colored stone grading system in the world yet, with many people in the gem trade opposing to its introduction. Many in the gem industry overlook the advantages of having a systematic colored stone grading system. The benefits are increased consumer confidence and sales. In order to develop a colored stone grading system, one need to create a simple language useful for easy communication so that the relative value can be determined by the market + the consumers benefit from it because of its simplicity.
Colored gemstone dealers have their own grading system (s), and most use terms such as AAA, AA, A, BBB, BB, B, CCC, CC, C and so on. Dealers may understand the gradation but consumers don't. There is also a link between the coffee beans sources and rock types. Like the origin of the coffee beans, rock types of gemstones does play a major role in understanding the color variances of high value stones such as diamonds, rubies (basalt vs marble hosted rocks), sapphires (basalt vs marble hosted rocks, emeralds (hydrothermal vs pegmatite vs metamorphic associations), tourmalines (pegmatite) and other colored stones. Though the concept may not be new to practising gemologists, its application via gem testing/grading laboratories could make a big difference, if used appropriately.
Comparing colored stones with coffee: There are similarities. There are no internationally accepted systematic colored stone grading system in the world yet, with many people in the gem trade opposing to its introduction. Many in the gem industry overlook the advantages of having a systematic colored stone grading system. The benefits are increased consumer confidence and sales. In order to develop a colored stone grading system, one need to create a simple language useful for easy communication so that the relative value can be determined by the market + the consumers benefit from it because of its simplicity.
Colored gemstone dealers have their own grading system (s), and most use terms such as AAA, AA, A, BBB, BB, B, CCC, CC, C and so on. Dealers may understand the gradation but consumers don't. There is also a link between the coffee beans sources and rock types. Like the origin of the coffee beans, rock types of gemstones does play a major role in understanding the color variances of high value stones such as diamonds, rubies (basalt vs marble hosted rocks), sapphires (basalt vs marble hosted rocks, emeralds (hydrothermal vs pegmatite vs metamorphic associations), tourmalines (pegmatite) and other colored stones. Though the concept may not be new to practising gemologists, its application via gem testing/grading laboratories could make a big difference, if used appropriately.
Treated Topaz: Bangkok
For some time there have been a significant increase in the volume of orange + reddish + pinkish brown topaz in the Bangkok market, and there are all sorts of rumors about its origin. Gem dealers have their own tales; some say they are Brazilian, while others claim they are African, Burmese and so on. The stones are not expensive so buyers from all corners of the world are buying them so that they can sell the stones on the internet, but many are not disclosing the color stability of the stones. And the fact of the matter is most specimens are unstable and upon exposure to direct sunlight for several hours, they fade to near colorless. Buyer beware!
Sunday, July 22, 2007
Blood Diamonds
(via History Channel) Diamonds are symbols of wealth, elegance and love around the world. But in several African nations, they have been a means to power, a reason to terrorize millions of innocent civilians, and may have even helped finance some of the world's most brutal terrorists. The human cost of the illicit global diamond trade is examined in the provocative documentary BLOOD DIAMONDS only on THE HISTORY CHANNEL @ http://www.history.com/minisites/blooddiamonds
I think it's one of the best documentary on blood diamonds.
I think it's one of the best documentary on blood diamonds.
The Scientific Gemmologist
2007: I like the snowcap on a mountain analogy. Gemology is gradually morphing, but the basic tenets remains the same. Today there are new analytical instruments for gemologist (s) to analyze and interpret, at a cost, but you still need a third eye to identify unknown gemstones with basic instruments. Today consumers want simplicity. They have no time nor the ability to understand the chemical, physical and optical properites of gemstones + experience alone is not enough; you need that 'otherness', that special feel for gemstones. It's a gift from the gods, and only a few have those skills.
(via The Journal of Gemmology, Vo.IX. No.6, April 1964) G V Axon writes:
The purpose of this article is to examine the current status of gemology, to make a few comments thereon, and to report a minor research project on distinguishing man-made from natural crystals.
There seems to be a general feeling among active gemologists that gemology as a science is somehow up against a brick wall. There is a great deal of useful, interesting, and informative writing, but there is a tendency to spread the well-known techniques over a greater area instead of developing new techniques to deal with problems which currently are without solution or present considerable difficulty even to experienced and highly regarded gemologists.
Thus to a newcomer, such as this writer, there seems a tendency to emphasize the obvious, to repeat the well-known, and to avoid facing up to the fact that gemology as a science needs a new structure in its intellectual basis—perhaps, in fact, a radical decision to recognize the existence of two types of gemologists. These are, of course, the ordinary trade gemologists and those who by reason of their training, interest, and experience are, in fact, scientific gemologists whether they are in the trade or not.
Gemology, today, is rather like a snowcap on a mountain. It is the most interesting part of the mountain. It sparkles in the sun like so many diamonds. It attracts mineralogists and geologists quite apart from members of the trade and trade laboratories, and hobbyists. One can well understand its attraction. But so many of those interested in the snowcap have never bothered to understand why the snow is there, and why it stays there. They are content to play with the snow and have a good time. They are simply not interested in understanding the massive structure on which the snowcap rests.
The result is that many in gem field are walking around on intellectual stilts and might topple over at any time. They would be hard put to explain why no chromium is found in the feldspars, and why fluorite and hydroxyl ions are found in silicate minerals such as topaz and tourmaline. This is not to criticize: it is merely to point out that gems are delightful things to study and handle, and that quite apart from this the vast majority of gemologists are not engaged in any fulltime capacity in the gem field. Even those who have qualified seldom dig deeper into the intellectual basis of gemology.
Of equal importance is the fact that gemology has long been regarded as a step-child of mineralogy. The basic reason for this, of course, is that the most valuable substances used as gems are minerals, and that, without minerals, gemology and the jewelry industry would be very much the poorer.
Yet since time immemorial many of the substances used in jewelry have been man-made. Ancient civilizations have yielded very many examples of man-made gems: they have yielded only a few valuable natural gemstones. Yet because the natural gemstones are the flowers of the mineral kingdom, gemology has had to be content with playing second fiddle to mineralogy.
Plainly, this is no longer acceptable. It is not only that natural gemstones, especially the finest, are becoming increasingly rare, but that the substances used as gems are increasingly varied and increasingly difficult to distinguish. Today, gemologists, having relied probably for far too long on mineralogists, are faced with having to reconstruct the intellectual basis of their profession. The problem is basically one for the scientific gemologists.
Clearly, the first approach must be to shift the intellectual basis of gemology away from the glittering and inviting snowcap to the uninviting and less glamorous rock base. There is a need for a far more fundamental approach to the study of gemology. It should surely start with the formation of the universe, the development of the elements, the formation of the earth, and how the elements came together to form various substances known as rocks, minerals and crystals.
As some gem material is of organic origin, there should be at least some attempt to explain, as far as possible, the development of organic from inorganic life, and the organic structure of the various organic gem materials.
Today, the gemologist is faced not only with a wide variety of man-made substances used as gems, but also with an increasingly wide range of man-made crystals. Only those gemologists who have had time to look into this growing field of man-made crystals can fully appreciate its extent. Not only is there a vast variety of crystals in element and compound form, but many of these crystals may be doped by other substances for various scientific and industrial purposes. It would be almost impossible for gemologists to keep up with the developments even if they had the time. As for distinguishing the man-made from the natural crystal material, it will obviously become more rather than less acute.
Even though many of these man-grown crystals are not suitable for use as gems, the intellectual problem remains. In the United States, especially, there are thousands of amateur lapidaries who are not too willing to test their skills on anything they can put their hands on, from man-grown crystals to coprolites. Sooner or later, these curiosities find their way to the gem trade laboratory.
It was with the intention of discovering any new techniques that inquiries were made of some two dozen crystal-growing firms and scientists in the United States. The idea sprang from a comment on Carbon 14 in correspondence to this writer from J R Jones of Sydney, Australia. It was thought that if techniques were so advanced in one field, perhaps similar techniques (without destroying the material, of course) could be applied to the gem field. There must surely be some differences between natural crystals, say sixty million years old, and crystals being grown this minute in factories and laboratories.
The enquiries yielded a meager harvest. Some of the comments received are listed below mainly out of curiosity. Only in one case, dealt with later, was a basically new idea (at least, new to this writer) advanced.
1. Synthetic quartz crystals cost about twelve times as much as natural quartz.
2. Synthetic quartz crystals often have complete faces whereas natural quartz crystals often have many faces missing.
3. Synthetic crystals are much purer as a rule.
4. Synthetic production techniques often use no water, whereas natural crystals have often been produced by hydrothermal forces. Thus they contain microscopic water pockets (partially filled vacuoles). Unfortunately, analysis techniques destroy the material.
5. The majority of man-made quartz is grown in a sodium hydroxide or sodium carbonate solution. Thus the sodium content is usually higher in the synthetic.
6. Synthetics show fewer absorptions when analyzed by infra-red spectrographic methods.
7. X-ray analysis, neutron activation, and electron and neutron diffraction, were also given as possible methods.
8. X-ray diffraction topography will show a greater concentration of dark lines in the synthetic when measured against a natural crystal. Spectrographic analysis, which requires the grinding of some of the material, usually shows a greater concentration of some elements in the synthetic.
Of particular interest is the electron paramagnetic resonance spectroscopy (EPR) developed by Varian Associates, Palo Alto, California, USA. Unfortunately, the instrument costs some $30000, and the fee quoted tentatively for each spectrum was $25. Although one test may not suffice for full identification, such a test may be able to establish that a gemstone was not natural.
The basis of EPR lies in minute chemical and structural anomalies. The extremely complex instrument is an extremely sensitive, non-destructive way of detecting impurity levels in crystals. A synthetic would be relatively pure. The result is basically a graph showing straight and jagged lines, hills, and valleys, which vary according to the structural perfection and molecular structure of the material analyzed.
According to the material supplied by the company, it is now possible to use the magnetic properties of electrons (as well as of nuclei) to reveal chemical structure and bonding characteristics.
Just as nuclei have charge, mass, angular momenta and magnetic moments, so do electrons, and it is upon this that EPR depends. If the electron has not only an intrinsic magnetic moment along its own spin axis, but also one associated with its circulation in an atomic orbit, the electron will possess a total magnetic moment equal to the vector sum of these magnetic moments. The ratio of this total magnetic moment to the spin value is constant for a given atom and environment, and is called the gyromagnetic ratio or spectroscopic splitting factor for that particular electron. The fact that these ratios differ for various atoms and environments and the fact that local magnetic fields depend on the structure of matter permit the spectral separation and study according to the method of electron paramagnetic resonance spectroscopy.
It must be emphasized that not all atoms and molecules are susceptible to such study. There must be a resultant electronic magnetic moment associated with the atom or molecule under investigation; for example, effects may be observed for electrons in unfilled conduction bands, transition element ions, odd molecules and free radicals, biradicals, color centers, radiation damage sites, impurities in semi-conductors, and triplet electronic states.
The principal components of the EPR spectrometer are an electromagnet, a sweep generator, a stable microwave oscillator, a resonant cavity, a bolometer or crystal detector for demodulating the microwave power reflected from the resonant cavity (for the sample), an audio amplifier and a phase-sensitive detector, and a graphic recorder.
Possibly, this instrument has not been used much, if at all, in gemology, but the descriptions given above may plant a seed in minds better prepared in gemology than that of this writer. Certainly the idea is of great theoretical interest in the crystal field, and it seems to offer possibilities to the gemologist. It is becoming quite impossible to determine, by ordinary gemological methods, the nature of all crystals. If the synthetics and man-made can be weeded out and certified as man-made, it should then at least be easier to concentrate on determining the nature of the natural crystal material.
(via The Journal of Gemmology, Vo.IX. No.6, April 1964) G V Axon writes:
The purpose of this article is to examine the current status of gemology, to make a few comments thereon, and to report a minor research project on distinguishing man-made from natural crystals.
There seems to be a general feeling among active gemologists that gemology as a science is somehow up against a brick wall. There is a great deal of useful, interesting, and informative writing, but there is a tendency to spread the well-known techniques over a greater area instead of developing new techniques to deal with problems which currently are without solution or present considerable difficulty even to experienced and highly regarded gemologists.
Thus to a newcomer, such as this writer, there seems a tendency to emphasize the obvious, to repeat the well-known, and to avoid facing up to the fact that gemology as a science needs a new structure in its intellectual basis—perhaps, in fact, a radical decision to recognize the existence of two types of gemologists. These are, of course, the ordinary trade gemologists and those who by reason of their training, interest, and experience are, in fact, scientific gemologists whether they are in the trade or not.
Gemology, today, is rather like a snowcap on a mountain. It is the most interesting part of the mountain. It sparkles in the sun like so many diamonds. It attracts mineralogists and geologists quite apart from members of the trade and trade laboratories, and hobbyists. One can well understand its attraction. But so many of those interested in the snowcap have never bothered to understand why the snow is there, and why it stays there. They are content to play with the snow and have a good time. They are simply not interested in understanding the massive structure on which the snowcap rests.
The result is that many in gem field are walking around on intellectual stilts and might topple over at any time. They would be hard put to explain why no chromium is found in the feldspars, and why fluorite and hydroxyl ions are found in silicate minerals such as topaz and tourmaline. This is not to criticize: it is merely to point out that gems are delightful things to study and handle, and that quite apart from this the vast majority of gemologists are not engaged in any fulltime capacity in the gem field. Even those who have qualified seldom dig deeper into the intellectual basis of gemology.
Of equal importance is the fact that gemology has long been regarded as a step-child of mineralogy. The basic reason for this, of course, is that the most valuable substances used as gems are minerals, and that, without minerals, gemology and the jewelry industry would be very much the poorer.
Yet since time immemorial many of the substances used in jewelry have been man-made. Ancient civilizations have yielded very many examples of man-made gems: they have yielded only a few valuable natural gemstones. Yet because the natural gemstones are the flowers of the mineral kingdom, gemology has had to be content with playing second fiddle to mineralogy.
Plainly, this is no longer acceptable. It is not only that natural gemstones, especially the finest, are becoming increasingly rare, but that the substances used as gems are increasingly varied and increasingly difficult to distinguish. Today, gemologists, having relied probably for far too long on mineralogists, are faced with having to reconstruct the intellectual basis of their profession. The problem is basically one for the scientific gemologists.
Clearly, the first approach must be to shift the intellectual basis of gemology away from the glittering and inviting snowcap to the uninviting and less glamorous rock base. There is a need for a far more fundamental approach to the study of gemology. It should surely start with the formation of the universe, the development of the elements, the formation of the earth, and how the elements came together to form various substances known as rocks, minerals and crystals.
As some gem material is of organic origin, there should be at least some attempt to explain, as far as possible, the development of organic from inorganic life, and the organic structure of the various organic gem materials.
Today, the gemologist is faced not only with a wide variety of man-made substances used as gems, but also with an increasingly wide range of man-made crystals. Only those gemologists who have had time to look into this growing field of man-made crystals can fully appreciate its extent. Not only is there a vast variety of crystals in element and compound form, but many of these crystals may be doped by other substances for various scientific and industrial purposes. It would be almost impossible for gemologists to keep up with the developments even if they had the time. As for distinguishing the man-made from the natural crystal material, it will obviously become more rather than less acute.
Even though many of these man-grown crystals are not suitable for use as gems, the intellectual problem remains. In the United States, especially, there are thousands of amateur lapidaries who are not too willing to test their skills on anything they can put their hands on, from man-grown crystals to coprolites. Sooner or later, these curiosities find their way to the gem trade laboratory.
It was with the intention of discovering any new techniques that inquiries were made of some two dozen crystal-growing firms and scientists in the United States. The idea sprang from a comment on Carbon 14 in correspondence to this writer from J R Jones of Sydney, Australia. It was thought that if techniques were so advanced in one field, perhaps similar techniques (without destroying the material, of course) could be applied to the gem field. There must surely be some differences between natural crystals, say sixty million years old, and crystals being grown this minute in factories and laboratories.
The enquiries yielded a meager harvest. Some of the comments received are listed below mainly out of curiosity. Only in one case, dealt with later, was a basically new idea (at least, new to this writer) advanced.
1. Synthetic quartz crystals cost about twelve times as much as natural quartz.
2. Synthetic quartz crystals often have complete faces whereas natural quartz crystals often have many faces missing.
3. Synthetic crystals are much purer as a rule.
4. Synthetic production techniques often use no water, whereas natural crystals have often been produced by hydrothermal forces. Thus they contain microscopic water pockets (partially filled vacuoles). Unfortunately, analysis techniques destroy the material.
5. The majority of man-made quartz is grown in a sodium hydroxide or sodium carbonate solution. Thus the sodium content is usually higher in the synthetic.
6. Synthetics show fewer absorptions when analyzed by infra-red spectrographic methods.
7. X-ray analysis, neutron activation, and electron and neutron diffraction, were also given as possible methods.
8. X-ray diffraction topography will show a greater concentration of dark lines in the synthetic when measured against a natural crystal. Spectrographic analysis, which requires the grinding of some of the material, usually shows a greater concentration of some elements in the synthetic.
Of particular interest is the electron paramagnetic resonance spectroscopy (EPR) developed by Varian Associates, Palo Alto, California, USA. Unfortunately, the instrument costs some $30000, and the fee quoted tentatively for each spectrum was $25. Although one test may not suffice for full identification, such a test may be able to establish that a gemstone was not natural.
The basis of EPR lies in minute chemical and structural anomalies. The extremely complex instrument is an extremely sensitive, non-destructive way of detecting impurity levels in crystals. A synthetic would be relatively pure. The result is basically a graph showing straight and jagged lines, hills, and valleys, which vary according to the structural perfection and molecular structure of the material analyzed.
According to the material supplied by the company, it is now possible to use the magnetic properties of electrons (as well as of nuclei) to reveal chemical structure and bonding characteristics.
Just as nuclei have charge, mass, angular momenta and magnetic moments, so do electrons, and it is upon this that EPR depends. If the electron has not only an intrinsic magnetic moment along its own spin axis, but also one associated with its circulation in an atomic orbit, the electron will possess a total magnetic moment equal to the vector sum of these magnetic moments. The ratio of this total magnetic moment to the spin value is constant for a given atom and environment, and is called the gyromagnetic ratio or spectroscopic splitting factor for that particular electron. The fact that these ratios differ for various atoms and environments and the fact that local magnetic fields depend on the structure of matter permit the spectral separation and study according to the method of electron paramagnetic resonance spectroscopy.
It must be emphasized that not all atoms and molecules are susceptible to such study. There must be a resultant electronic magnetic moment associated with the atom or molecule under investigation; for example, effects may be observed for electrons in unfilled conduction bands, transition element ions, odd molecules and free radicals, biradicals, color centers, radiation damage sites, impurities in semi-conductors, and triplet electronic states.
The principal components of the EPR spectrometer are an electromagnet, a sweep generator, a stable microwave oscillator, a resonant cavity, a bolometer or crystal detector for demodulating the microwave power reflected from the resonant cavity (for the sample), an audio amplifier and a phase-sensitive detector, and a graphic recorder.
Possibly, this instrument has not been used much, if at all, in gemology, but the descriptions given above may plant a seed in minds better prepared in gemology than that of this writer. Certainly the idea is of great theoretical interest in the crystal field, and it seems to offer possibilities to the gemologist. It is becoming quite impossible to determine, by ordinary gemological methods, the nature of all crystals. If the synthetics and man-made can be weeded out and certified as man-made, it should then at least be easier to concentrate on determining the nature of the natural crystal material.
Hemimorphite
Chemistry: Zinc silicate
Crystal system: Orthorhombic; double termination, but of different orientation (hemimorphic); tabular and thin striated crystals; fan-shaped aggregates; massive material granular or fibrous, banded or stalactitic.
Color: Transparent to opaque; commonly banded blue or green; colorless or white, also violet, gray, yellow and brown.
Hardness: 4.5 - 5
Cleavage: Perfect: 1 direction; Fracture: brittle, conchoidal to sub-conchoidal.
Specific gravity: 3.4 – 3.5
Refractive index: 1.63 mean; 1.614 – 1.636; Biaxial positive; 0.022
Luster: Vitreous, silky to dull.
Dispersion: -
Dichroism: -
Occurrence: Secondary mineral in oxidation; oxidation zone of zinc containing ore bodies; Italy, Mexico, Namibia, Algeria.
Notes
Usually associated with smithsonite; massive may look like smithsonite, chrysocolla or turquoise; colorless (rare); crystals faceted for collectors; massive blue material cut cabochon.
Crystal system: Orthorhombic; double termination, but of different orientation (hemimorphic); tabular and thin striated crystals; fan-shaped aggregates; massive material granular or fibrous, banded or stalactitic.
Color: Transparent to opaque; commonly banded blue or green; colorless or white, also violet, gray, yellow and brown.
Hardness: 4.5 - 5
Cleavage: Perfect: 1 direction; Fracture: brittle, conchoidal to sub-conchoidal.
Specific gravity: 3.4 – 3.5
Refractive index: 1.63 mean; 1.614 – 1.636; Biaxial positive; 0.022
Luster: Vitreous, silky to dull.
Dispersion: -
Dichroism: -
Occurrence: Secondary mineral in oxidation; oxidation zone of zinc containing ore bodies; Italy, Mexico, Namibia, Algeria.
Notes
Usually associated with smithsonite; massive may look like smithsonite, chrysocolla or turquoise; colorless (rare); crystals faceted for collectors; massive blue material cut cabochon.
Saturday, July 21, 2007
Colored Stone Update
Colored stone markets are growing. The prices for top quality rubies are too expensive with supply getting difficult. Today Burma and Sri Lanka are the key sources for good quality colored stones + buying rubies and sapphires from the Burmese or Sri Lankan in their territory is not an easy task. They really know the world prices and bargain hard + they have also learned how to say No. Other colored stone species and varieties are also becoming popular. The prices for top quality Colombian emerald have increased more than 25%. Fancy sapphires are popular and selling well. Amethyst, citrine, garnet, tourmaline, topaz, ziron, feldspar have all become popular choices for regular markets + television and internet-based retailers have also helped to promote colored stones. They have made a significant impact, because they not only educate consumers by expanding the gemological vocabulary beyond the mainstream colored stones but also on pricing. Consumers have now become familiar with less known colored stones such as sphene, sphalerite, Paraiba-type tourmalines, zircon, peridot, spinel and much more + new treatments, synthetics and imitations. Unique designers have also adapted to the changing trends promoting colored stones. Consumers are gradually becoming like 'little Buddhas'.
DTC Ombudsman Starts Cleansing Role
Chaim Even-Zohar writes about the new supplier of choice methodology + the role of DTC Key Account Managers and their periodic reviews about their clients + Dermot Gleesson effect + other viewpoints @ http://www.idexonline.com/portal_FullEditorial.asp
Are You Looking At Prices or Art?
Eileen Kinsella writes about the state of mind of the collectors and their ability (or inability) to look at a work, appreciate it, and evaluate it in and of itself + other viewspoints @ http://artnews.com/issues/article.asp?art_id=2268
Again there are similarities between pricing of gemstones and art. Both are subjective concepts. A piece of art or gem always have nice stories with them + they are have their special beauty. You need a third eye to see through, appreciate and evaluate. You also need expertise, meaning you need to understand how gems or art are bought and sold. If you don't have the product knowledge or don't want to take the time to learn, then you need an expert that you trust to make the judgment for you. I think most of today's buyers are collectors with a passion for gems or art and want to know everything they can about them. Some may even become too addicted; they would never part with these stones or art at any price.
Again there are similarities between pricing of gemstones and art. Both are subjective concepts. A piece of art or gem always have nice stories with them + they are have their special beauty. You need a third eye to see through, appreciate and evaluate. You also need expertise, meaning you need to understand how gems or art are bought and sold. If you don't have the product knowledge or don't want to take the time to learn, then you need an expert that you trust to make the judgment for you. I think most of today's buyers are collectors with a passion for gems or art and want to know everything they can about them. Some may even become too addicted; they would never part with these stones or art at any price.
Two Tricky Items
2007: I have gone through a similar situation during the course of my work, and I believe gemstones will continue to teach us one way or the other.
(via The Journal of Gemmology, Vol.IX, No.9, January 1965) G V Axon writes:
The pleasure one gets from guessing an identification and then proving it to be correct is always to be offset by the tendency to read the various gem instruments incorrectly with the guess uppermost in mind. Two stones recently gave the author a rather sharp lesson.
The first stone, about half-a-carat, was bright green, and with ‘horse-tail’ inclusions. The stone appeared pink with red flashes under the ordinary color filter, and even in ordinary light without the filter appeared to give off red flashes. The second stone, of some 22 carats, was quite a lively brown.
The first guess was demantoid garnet. The stone turned out to be chrome sphene. The second guess was heat treated amethyst. The stone was golden calcite. Neither chrome sphene nor golden calcite is seen frequently, the former because it is still rather rare, and the latter because it is so difficult to cut and so fragile.
Here were two very good examples of tricky looks. Of course, closer examination would have revealed that the horse-tail in chrome sphene did not appear to radiate, and that the doubling of the back facets in the calcite was apparent. The same would no doubt apply to a small clean chrome sphene examined under 10x lens.
Both stones were extremely tricky items, to say the least, for the horse-tail inclusion of demantoid has practically become its most single identification, yet here was a stone with very similar inclusions and almost identical in appearance. Thus ‘horse-tail’ inclusions will have to be watched rather more closely now.
As for golden calcite, so few specimens are to be seen that few jewelers will ever encounter them. Even so, heat treated amethyst is by now almost recognizable at sight—at least I thought it was, but after the shock of receiving a golden calcite and finding what appeared to be a heat treated amethyst, I have again learned the importance of never taking anything for granted, and of always making at least to tests, excluding the first ‘informed guess.’
(via The Journal of Gemmology, Vol.IX, No.9, January 1965) G V Axon writes:
The pleasure one gets from guessing an identification and then proving it to be correct is always to be offset by the tendency to read the various gem instruments incorrectly with the guess uppermost in mind. Two stones recently gave the author a rather sharp lesson.
The first stone, about half-a-carat, was bright green, and with ‘horse-tail’ inclusions. The stone appeared pink with red flashes under the ordinary color filter, and even in ordinary light without the filter appeared to give off red flashes. The second stone, of some 22 carats, was quite a lively brown.
The first guess was demantoid garnet. The stone turned out to be chrome sphene. The second guess was heat treated amethyst. The stone was golden calcite. Neither chrome sphene nor golden calcite is seen frequently, the former because it is still rather rare, and the latter because it is so difficult to cut and so fragile.
Here were two very good examples of tricky looks. Of course, closer examination would have revealed that the horse-tail in chrome sphene did not appear to radiate, and that the doubling of the back facets in the calcite was apparent. The same would no doubt apply to a small clean chrome sphene examined under 10x lens.
Both stones were extremely tricky items, to say the least, for the horse-tail inclusion of demantoid has practically become its most single identification, yet here was a stone with very similar inclusions and almost identical in appearance. Thus ‘horse-tail’ inclusions will have to be watched rather more closely now.
As for golden calcite, so few specimens are to be seen that few jewelers will ever encounter them. Even so, heat treated amethyst is by now almost recognizable at sight—at least I thought it was, but after the shock of receiving a golden calcite and finding what appeared to be a heat treated amethyst, I have again learned the importance of never taking anything for granted, and of always making at least to tests, excluding the first ‘informed guess.’
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