Emeralds; The God's Shed Green Tears

The Emerald of Colombia Part I

By Richard W. Wise, G.G.

Green Gold:

There they sat, scattered like match sticks across the white desk blotter, glowing a rich cool green in the late afternoon sun. My breath catches in my throat. I do my best to maintain my cool, to politely keep my eyes on those of my host, a suave youngish Colombian businessman in a white dress shirt, the jacket of an expensive pin-striped suit thrown over the back of his desk chair. “Youngish” is, of course, a relative term when you’re pushing 63. The dealer smiles and motions me to a seat and there they were right in front of me, a king’s ransom of emerald crystals. I try not to dwell on the four tough looking guys with the semi-automatic rifle in the room we passed though on the way into the office. They too wore nice suits.

This was a sight I never expected to see. I have traveled all over the world and seen a number of exceptional gemstones but never have I seen a rough parcel of such high quality of anything, anywhere, never mind gem emerald. I pick up one crystal, it is a bit distorted in form but it is clean and the size of my thumb. I hold it up to the light. Completely clean a medium dark slightly bluish green. I do notice an interesting pattern of zoning, several thin dark lines, almost black, that run perpendicular to the length of the crystal.

“That one cost me $35,000”, the dealer volunteers.

“How much does it weigh”, I ask.

He places the crystal on a scale. I do a quick calculation. The price comes to $1, 411.00 per carat.

The dealer, perhaps regretting his candor with the inquisitive American author, hastens to add that the average yield in cut stones is only about 25%.

Point taken!, that means the average cost of the parcel after cutting works out to $5,644.00 per carat. This is beginning to sound like a multi-million dollar crap shoot because, as we are about to witness, this parcel contains a range of qualities.

Columbia’s Top Cutter:

Senor Adolpho Argotty is considered Columbia’s top emerald cutter. Now 55 he began cutting when he was 15 years old. His father wanted to be a cutter but was not very good at it. Argotty laughs, “so he became a teacher.”

We have been invited to watch Senor Argotty cut two rough crystals from the big La Pita parcel; one weighs 7.17 carats the other 8.53 carats. Argotty works by hand, literally! After examining the two crystals for a few minutes he takes one and casually puts it to the wheel. I see no scales, no calipers, no jam-peg, no measuring devices of any kind, not even a ruler.

The first step is called pre-forming; it is the most important step and requires the highest degree of skill. The wheel is charged with diamond grit mixed with water. The pre-former decides what to keep and what to cut out and that determines the shape and weight of the finished gem. The facets will be added later.

Next: Argotty puts it to the wheel! Stay tuned.

Learn the truth about how Emeralds and other fine gems are graded and priced!

Follow me on gem buying adventures in the pearl farms of Tahiti. Visit the gem fields of Australia and Brazil. 120 carefully selected photographs showing examples of the highest quality gems to educate the eye, including the Rockefeller Sapphire and many more of the world’s most famous gems. Consider my book: Secrets Of The Gem Trade, The Connoisseur’s Guide To Precious Gemstones.

“Wise is a renowned author… He’s
done a marvelous job of this first book, monumental work, a tour de force…My recommendation: Buy this book”.

Charles Lewton-Brain, Orchid

whether you like to know what the best colour is in Tanzanite, or how to grade a Diamond, you will find it in this book. No other book I read before dealt with this topic is such detail as Richard Wise’s masterpiece.”

A. Van Acker, FGA
Amazon June 2005

“Secrets Of The Gem Trade: The Connoisseurs Guide To Precious Gemstones by Richard W. Wise is an impressive new reference for dedicated dealers and collectors of gems, gemstones, and … pearls. Introducing and descriptively exploring each and every gem covered in the easy-to-use reference, Secrets Of The Gem Trade contains an illustrated summary of each stone inclusive of its history and general information, hue and tone, saturation, which may be noticed as the finest, an understanding of the particular gems rarity, and the caution for synthetics and how to depict them, however depending upon the stone there may be description of clarity, color fading, multi-color effect, etc. Secrets Of The Gem Trade is very highly recommended to anyone interested in gemology as a superbly organized, authoritative, comprehensive, and easy-to-follow reference.”

Midwest Book Review
April 2006

Only $37.95. Read a couple of chapters online: www.secretsofthegemtrade.com.

Buy it on Amazon: www.amazon.com

Asking to see the Pigeon’s blood is like asking to see the face of God"

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About once a month on one of the gem forums someone asks the question:

"What color is pigeon's blood."

by Richard W. Wise, G.G.

The real question is, of course, "what is the best color in ruby." Although I cover the question in some depth in my book; Secrets of The Gem Trade, The Connoisseur's Guide to Precious Gemstones, it appears that a few people have yet to read the book. (pictured above a gem quality 2.09 carat natural old mine Burma ruby with a GRS "pigeon's blood certificate)

The short answer is simply that rubies should be red. Problem is there are almost no visually pure color in nature so, we speak of a mixture of colors. In gems, we normally speak of a primary and a secondary color or hue. Gems may have more than two hues but it it is difficult for even the most discerning connoisseur to see more than two. Still a ruby must be predominantly red, that is, have a primary red hue. Put another way in the color mix, red must be at least 51% of the hue mixture. If its not red its not a ruby. Any member of the gem family corundum that is any color other than red we call sapphire.

Ruby may exhibit one of a few possible secondary hues. These are: pink, purple and orange. Purple and orange are the hues immediately adjacent to red on the color wheel. You will never find a ruby with a green secondary hue. Pink, a paler less saturated red is also possible. The finest color or pigeon's blood exhibits a purple secondary hue. Why purple, there are two good reasons; one historical and the other based upon color science.

This historical explanation I owe to Vincent Pardieu. Vincent began by studying gemology in Burma and he found a dealer who explained "pigeon blood" to him. The Burmese coined the term. Purple is a hue that falls between blue and red on the color wheel. It is known scientifically as a modified spectral hue.

The Burmese set gems in pure gold which is a a very rich yellow color. Blue is the compliment of red. Complimentary colors are those that cancel each other out. So when a purplish red ruby is set in yellow, the yellow of the metal cancels out the blue in the purple leaving behind, guess what an almost visually pure red.(pictured above a 1.63 carat gem quality old mine Burma ruby with a GRS "pigeon's blood certificate). So the goal for the Burmese is red, pure red! See more!

I wrote my book several years before I met Vincent in Bangkok. However, I reached the same conclusion by applying a logical analysis. My reasoning goes something like this. Color Science teaches that the color red reaches its optimum saturation (brightness) at a fairly dark tone, somewhere about 80%. This is not opinion, it is measurable scientific fact. If you consider that 100% tone would be pure black, 80% is pretty dark. Pink and orange on the other hand reach their optimum saturation at fairly light tones. Pink obviously as it is by definition paler (less bright). Orange reaches its optimum saturation at between 30-40% tone.

Purple reaches its optimum saturation at around 60% tone. Now, if you add a light pigment to a dark paint you would obviously lighten the overall effect. Same is true in transparent media. The optimum tones of red and purple mix fairly well both being both dark in tone. The purple unlike the pink does not dilute the red. Pink and orange would lighten the red thus reducing the overall saturation of the pinkish-red or orangy-red color. Purple reinforces the red, orange and pink dilute. Make sense? Not everyone agrees. Some connoisseurs like a bit or orange. They feel it frames and pumps up the red hue. A good point if you consider the effect of orange in red spinel. Be that as it may, for good historical as well as scientifically verifiable reasons, orangy red is not pigeon's blood.

The first image above is of a 2.09 carat Burmese natural ruby from the old min at Mogok. This stone has a bit purer red, exhibits less purple than the second stone, a 1.63 carat gem from the same mining area. Both, however, have been grading "Pigeon's blood" by GRS, Swiss Lab, Bangkok. As you might imagine this lab sees an awful lot of rubies. Both stones are from the Mogok Valley, this is the place, going back to the Bronze Age, where the original stones were mined back when the term pigeon's blood was coined. A lot of the gems currently in the market are from a new mining areas Mong Hsu that is about half way between Mogok and the Thai border. Mong Hsu stones can certainly be pigeon's blood color but since we are talking about a historical term I thought it best to use illustrations from the old mine.

With the discovery of new sources of ruby in Africa a controversy has arisen over use of the term pidgeon's blood to describe the color of gems most specifically from Mozambique. The Chinese have outright banned the use of the term for ruby other than those of Burmese origin.

At the 2012 Hong Kong show I purchesed two exceptional unheated gems from Mozambique that were described in a GRS report as "vivid red" with a color identical to Burmese stones with GRS Pidgeon's Blood certificates. If, as I have suggested here and in my book, pigeon's blood is a definable hue then it seems to me that any ruby that meets those criteria can and should be labeled the same.

Want to Learn more?

Follow me on gem buying adventures to the old Burma ruby mine at Mogok. Learn how to judge the quality of rubies, sapphires, emeralds, garnets and 31 other gems. 120 carefu
lly selected photographs showing examples of the highest quality gems to educate the eye, including the Rockefeller Sapphire and many more of the world's most famous gems. Consider my book: Secrets Of The Gem Trade, The Connoisseur's Guide To Precious Gemstones.

“Wise is a renowned author… He’s
done a marvelous job of this first book, monumental work, a tour de force…My recommendation: Buy this book”.

Charles Lewton-Brain, Orchid

A. Van Acker, FGA
Amazon June 2005

"Secrets Of The Gem Trade: The Connoisseurs Guide To Precious Gemstones by Richard W. Wise is an impressive new reference for dedicated dealers and collectors of gems, gemstones, and … pearls. Introducing and descriptively exploring each and every gem covered in the easy-to-use reference, Secrets Of The Gem Trade contains an illustrated summary of each stone inclusive of its history and general information, hue and tone, saturation, which may be noticed as the finest, an understanding of the particular gems rarity, and the caution for synthetics and how to depict them, however depending upon the stone there may be description of clarity, color fading, multi-color effect, etc. Secrets Of The Gem Trade is very highly recommended to anyone interested in gemology as a superbly organized, authoritative, comprehensive, and easy-to-follow reference."

Midwest Book Review
April 2006

Now 20% off. Read a couple of chapters online or buy one of the few remaining limited editons: www.secretsofthegemtrade.com.

Buy it on Amazon: www.amazon.com

Labels: gem prices, gemstones, new gem strike, spinel prices, Tanzania gems, Tanzanian Spinel

Book Review: American Cut, The First 100 Years by Al Gilbertson

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by Richard W. Wise
©2007

Al Gilbertson, G.G.
The Gemological Institute of America
Paperback, 214 Pages. $29.95

American Cut, The First 100 Years, sets the record straight. Al Gilbertson tells the true story of the development of the ideal cut round brilliant diamond. First, Gilbertson clears away the prevailing myth endlessly repeated by industry writers, including this one, that Marcel Tolkowsky was the first to articulate the proper proportions for fashioning a round brilliant cut diamond.

Gilbertson has done his homework. He traces the origin of a finely cut diamond from its origins in Early European history to a maverick American jeweler by the name of Henry Morse. Morse, a jeweler not a cutter, opened a diamond cutting shop in Boston around 1860. Morse had the idea that improving the cut of a diamond would result in a more beautiful stone and that better looking stones would sell better. This revolutionary concept brought him in direct conflict with his own employees, diamond cutters educated in Europe where cutters were actually fined if they lost too much weight cutting a diamond.

The author makes the point, not unknown to young men shopping for an engagement ring today, that in diamonds, better meant bigger. From earliest times, European monarchs were in competition with one another to own the biggest diamonds. The ownership of a big rock was a status symbol that added luster to a reign not to mention being a highly portable source of ready money. Not everyone agreed, Louis XIV, the biggest gem collector of them all, ordered his jeweler, Pitau to recut the French Blue from a hefty 114 carats to a mere 66, a loss of 41%, simply to improve its sparkle.

Morse has the good luck to hire a fellow named Charles Field, as his shop foreman. Field invented a mechanical diamond bruting machine that replaced the old method of hand rounding, a laborious process of hand rubbing that required weeks to shape a single gem. Morse experimented with a series of cutting angles and by 1870 had discovered crown and pavilion angles that dramatically improved face-up appearance. Morse and Field then invented a gauge to be used by their cutters to achieve the true precursor of modern “ideal cut” round.

There is a whole lot more. Gilbertson takes us right to the present discussing the influence of Tolkowsky and American pioneer gemologists, Frank Wade and GIA founder Robert Shipley. Gilbertson’s own insights into beauty and diamond cutting are of real interest. He was part of the team that researched over 70,000 sets of proportions that led to the new GIA diamond cut evaluation system and knows whereof he speaks.

Profusely illustrated, well researched and thoughtfully written, American Cut, The First 100 Years gives us the real story. It is one of those books that deserve a place of every gemologist’s library. At $29.95 it is a bargain. Order here

Ordered American Cut, The First 100 Years? Still have a few dollars left?

Follow me on gem buying adventures in the pearl farms of Tahiti. Visit the gem fields of Australia and Brazil. 120 carefully selected photographs showing examples of the highest quality gems to educate the eye, including the Rockefeller Sapphire and many more of the world’s most famous gems. Consider my book: Secrets Of The Gem Trade, The Connoisseur’s Guide To Precious Gemstones.

“Wise is a renowned author… He’s
done a marvelous job of this first book, monumental work, a tour de force…My recommendation: Buy this book”.

Charles Lewton-Brain, Orchid

A. Van Acker, FGA
Amazon June 2005

Midwest Book Review
April 2006

Only $37.95. Read a couple of chapters online: www.secretsofthegemtrade.com.

Buy it on Amazon: www.amazon.com

Giant Crystals found at Tanzanian Gem Fields

Gem Prices follow Real Estate in the New Gilded Age

Tourmaline: Copper, copper, whose got the copper?

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You can’t smell it, you can’t taste it, you can’t see it but its presence or absence can make a difference of tens of thousands of dollars in the price of a tourmaline. What is it? Copper!

By Richard W. Wise

In late 1990 copper bearing tourmaline from Paraiba first entered the market. In 1991 I wrote an article for Colored Stone “Tourmaline, A Modest Proposal” in which I predicted that just as Paraiba had established a tourmaline aristocracy, inevitably stones that exhibited the light to medium saturation and hue similar to Paraiba stones would escalate in price. What I did not anticipate and could not predict was the discovery of Paraiba-like-copper-bearing- tourmaline in Nigeria and Mozambique. (Pictured above left 0.88 Paraiba tourmaline from Brazil from the R. W. Wise collection.)

Prices have, indeed, escalated and the hierarchy has been established. Regardless of the quality of the stone, genuine Brazilian stones from the Paraiba mining region will bring the highest prices followed by Mozambique followed by Nigeria. (Pictured below right: 14.70 carat pair of pear shaped Mozambique cuprian tourmalines. Cutting Edge Award Winners, sold) Problem is, areas such as Afghanistan are producing vivid blue green non-cuprian gems that are superior to some of the cuprian stones. What determines the price, beauty, oh no, its all about the copper. We have become inured to such absurdities in the ruby, sapphire and emerald markets but Virgina its only a tourmaline! (pictured below left 3.97 carat Afghan non-copper bearing blue tourmaline from the R. W. Wise Collection)

So at every booth in Hong Kong showing a pretty blue green tourmaline. What was the first question? “Is it copper bearing?” Without asking that question is was impossible to price the stone.

Staggering Prices Differentials:

Price differentials can be staggering. The 14.70 pair of pear shapes pictured above right are certainly the finest of the Mozambique stones yet they sold at a price that was less than half what a comparable, if you could ever find a comparable, pair of Brazilian Paraiba stones would bring. Stones that compare in beauty but are not copper bearing bring hundreds of dollars while copper bearing look-alikes command prices into the low thousands of dollars per carat.

Whats New on our website:

Still haven’t given up my day job. Just finished uploading a number of new pieces to our online catalogue. Several new tourmalines plus sapphires and some lovely new and antique jewelry pieces. www.rwwise.com

Whats a buyer to do?

Follow me on gem buying adventures in the pearl farms of Tahiti. Visit the gem fields of Australia and Brazil. 120 carefully selected photographs showing examples of the highest quality gems to educate the eye, including the Rockefeller Sapphire and many more of the world’s most famous gems. Consider my book: Secrets Of The Gem Trade, The Connoisseur’s Guide To Precious Gemstones.

“Wise is a renowned author… He’s
done a marvelous job of this first book, monumental work, a tour de force…My recommendation: Buy this book”.

Charles Lewton-Brain, Orchid

A. Van Acker, FGA
Amazon June 2005

Midwest Book Review
April 2006

Only $37.95. Read a couple of chapters online: www.secretsofthegemtrade.com.

Buy it on Amazon: www.amazon.com

Hong Kong Gem & Jewelry Show 2007

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Prices at the 2007 Hong Kong Show

by Richard W. Wise

Dateline Hong Kong.

This Thursday the Hong Kong Post reported that the U. S. dollar had reached a historic low against most major world currencies. Perhaps more important, the dollar which has been steadily losing ground against the Thai baht since its 2001 high, recently went into freefall. Historic data. Although the dollar along with the euro remains the international currency of choice, Bangkok is the capital of the colored gemstone trade and Thai dealers think in baht and the dollar has lost 19% against the Thai currency since the September 2006 show.

Ruby & Sapphire:

That said, prices of ruby and sapphire that were up dramatically in dollar terms at last year’s show ( read my 2006 report) have shown little upward movement. This is possibly the result of very poor sales at this September’s Bangkok show and would seem to indicate that Asian dealers are reluctant to pass along additional increases to a U. S. market currently viewed as on the edge of recession. The September Hong Kong show is one of the big three, the triumvirate of shows that sets future market prices. It will be interesting to see if dealer’s restraint will last until the all important Tucson shows in February particularly if the dollar continues to slide.

As usual, dealers report that supplies are down, particularly for high quality Burmese ruby and sapphire. This is the gem dealer’s eternal lament and one is tempted to ask; “yeah right, so what else is new” except that a new pro-democracy movement has apparently broken out in Burma with thousands of people taking to the streets in the country’s two major cities Burma news updates. This has got to have a negative effect on supply, short term. Will the brutal crackdown that is sure to follow lead to new economic sanctions or a boycott of Burmese goods in the U. S. is difficult to predict.

The gemstone business in Burma exists on two levels; on the one hand large scale mining is in the hands of the government. If you are doing large scale mining, you are in business with the army and much of the important material mined in large scale operations is marketed through the semi-annual government auctions. But, gem mining is mostly a cottage industry. At least 50% of the gems produced are from small scale mom and pop ventures that fall beneath the government’s radar and is smuggled out of the country. Having been on buying trips to Burma, it is my opinion that any new sanctions will probably backfire and impact the small scale subsistence miner more than the generals.

Stay tuned.

Interested in understanding more about the grading of fine diamond, pearl and othe gems? Follow me on gem buying adventures in the pearl farms of Tahiti. Visit the gem fields of Australia and Brazil. 120 carefully selected photographs showing examples of the highest quality gems to educate the eye, including the Rockefeller Sapphire and many more of the world’s most famous gems. Consider my book: Secrets Of The Gem Trade, The Connoisseur’s Guide To Precious Gemstones.

“Wise is a renowned author… He’s
done a marvelous job of this first book, monumental work, a tour de force…My recommendation: Buy this book”.

Charles Lewton-Brain, Orchid

Only $37.95. Read a couple of chapters online: www.secretsofthegemtrade.com.

Buy it on Amazon: www.amazon.com

Off to Hong Kong

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by Richard W. Wise

This year I will be doing several projects for Colored Stone Magazine. To begin with I will be writing a market survey piece on the Hong Kong Gem and Jewelry Show. I love Hong Kong; hotels are reasonable, choice of restaurants amazing and the city fairly pulses with life. For those of you who visited Hong Kong a few years ago, things have changed. Remember those cute little umbrellas and those cheap silk embroidered dresses with the slits up the side well forget-about-it-gringo! In Hong Kong today the ladies shop Bally, Cartier and Prada. Believe it or not there are more Prada & Bally stores in Hong Kong than in the entire continental U. S.

The September Hong Kong is one of the big three shows. What goes on in Hong Kong Gem & Jewelry Show often sets the tone for Tucson and Basil. Last year, you’ll recall, I did a blog on pricing of cuprian, aka Mozambique “Paraiba” tourmaline. This year the net will be cast a bit wider.

David Federman has taken over as the helm at Colored Stone. For those who don’t know, David is the gem trade’s premier journalist. He is the author of several books and, without doubt, one of the most knowledgeable people out there. Look for some interesting changes at Colored Stone.

We are still working out the details but I believe you will be seeing my report online at Colored Stone’s website: www.colored-stone.com

I will be making a trip to the gem mines of Colombia in December and following up with a piece on old mine emeralds later in the year and with luck teaming up with that globe trotting French gemologist, Vincent Pardieu, for another series on exotic locals. Stay tuned.

Diamonds, diamonds and more diamonds!

Those of you who know me also know I am not a big fan of colorless diamonds. On the other hand, since 95% of the gems sold in the U. S. are, you guessed it, colorless diamonds, it behooves a jeweler to pay a bit of attention.

For the past decade, the big emphasis in diamond has been cut. We have seen the emergence of the super-ideal round and princess cut. Many new shapes have entered the market. As of 2002 there were 81 patented proprietary diamond cuts, 21 of which have been patented in the past decade. As of the same year there were no less than 23 “ideal”-cut brand names 15 of which were registered trade marks.

Many of these new cut represents attempts by manufactures to preserve eroding profit margins by offering a cut a gemstone that was unique to them. The new branded cuts come with a variety of names; escada, elara, linz, skystar and tycoon. I can not claim to have seen them all but the ones I have seen I have found not very exciting at all.

Two years ago passing Phillip Youngman’s booth at AGTA gem show in Tuscon I saw one that really rocked my world it is called Excalibur. Youngman has been a cutter for over thirty years. In that time he has developed a reputation as being one of the world’s best. Youngman cuts weather in sapphire, garnet or tanzanite are breathtaking.

I first met him about twenty years ago on Gemstone Row at the old GLDA show. Phil gave me my first lesson in buying rough. After I saw his cutting, he was usually sold out half way through the show, I quickly bought a couple of big rhodolite nodules, the twenty-fifty gram monsters that used to come out of the Umba River Valley back when East Africa was just being discovered as a gemstone producing region. The rough looked great when you held it to the light. Phil shook his head sadly; “Richard”, he said, “you don’t want me to cut these stones, they are going to be much too dark.” “Too dark?” “Yes”, then he proceeded patiently to show me the proper way to look at rough gemstones. Its a lesson I have never forgotten.

Fast forward to Tucson 04, Phil had several of his new cuts, he also has developed a round he calls Passion Flower, the interesting thing about these stones is that they seemed to follow me, they didn’t wink out as soon as I passed the perpendicular view. Unlike most well cut diamonds that look great when viewed perpendicular to the table, these stones still looked good 5-10 degrees off axis. And the dispersion! Most of you know that both The Gemological Institute of America GIA) and The American Gem Society Lab (AGS) spent much of the past decade researching the so-called ideal cut round. In the process GIA created a computer program that traced light return in 10,000 sets of theoretical proportions. The result; what I dubbed in 1991 the “super ideal cut.”

Is it truly super?, you bet its the world’s champion of total light return, that means it returns around 95% of the light that enters the crown of the stone back to the eye in the form of brilliance. Unfortunately in the process of maximizing brilliance, the super ideal has lost its soul. That last point may require a bit of explanation.

Bril
liance in a diamond is one of the two major characteristics that makes a diamond beautiful. The other dispersion, the break up of light into its constituent rainbow parts. Most of the new ideals seem to have sacrificed dispersion for light delivery and sacrificed a great deal in the process. The Excalibur has not!

As part of the twenty year process that produced his two patented cuts, Youngman has developed a diamond that seems to maximize both brilliance and dispersion without sacrificing either. How?, by paying attention to how the diamond looks as it moves! The programs used to develop the super ideal was basically static. Youngman’s objective was, by contrast, dynamic. Hey the finger moves! Eighty-five percent of the diamonds sold today end up on the finger and it is on the finger, in motion that Youngman’s cuts shine. Both have the high crown and small table that many connoisseurs appreciate in the Old European and Old Mine Cuts.

Excalibur and Passion Flower have both been tested by GemEx, a company that grades diamonds by using a machine called a brilliancescope to measure brilliance, dispersion and scintillation. Excalibur achieves the highest grades, Very High, in all three categories; Passion Flower grades on the line between high/very high in brilliance (white light return) and scintillation and very high in dispersion (colored light return).

Unlike most of the new proprietary cuts, that are simply not different enough to achieve patent status, in 2004 Youngman was granted design patents on both Excalibur and Passion Flower. In addition he has been granted registered trade marks on his “Ultimate Square Diamond” and “Ultimate Round Diamond” slogans.

I think I am in love!

“Wise is a renowned author… He’s
done a marvelous job of this first book, monumental work, a tour de force…My recommendation: Buy this book”.

Charles Lewton-Brain, Orchid

Only $37.95. Read a couple of chapters online: www.secretsofthegemtrade.com.

Buy it on Amazon: www.amazon.com

Golconda Diamonds Part II

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The Legendary Blue-White Diamonds, Rarest of them All

by Richard W. Wise

Just recently it was my good fortune to examine one of the legendary diamonds of Golconda. These gems were originally mined in India in the 16th-18th Centuries. The mines were tapped out by about 1725. Many of the world’s most famous diamonds, including the Regent and the Sancy (pictured above right), The Hope and the Koh-i-Noor came from the mines of Golconda. This gem was accompanied by a GIA certificate rating it D Flawless, the highest possible diamond grade and a Gublin Laboratory certificate that identified the stone as a Type IIa. (Regent above left, Sancy above right)

As discussed in my previous post, recent scientific analysis has shown that diamonds with proven Golconda provenance are of a specific type of rare, pure carbon diamond known as Type IIa. Less than 1% of the world’s diamonds are Type IIa. Scientifically speaking, Type IIa diamonds are an almost pure carbon diamond containing no significant amount of nitrogen in the crystal lattice. Nitrogen is the impurity in diamond that imparts the yellowish hue. The lack of yellow makes for a pure colorless (D,E,F) color diamond. Some experts claim that all Golconda diamonds are Type II. There is, as far as I know, no scientific evidence to back up that claim.

Blue-White Beauty:

Golconda stones are the true blue white diamonds of legend. Today, dealers use the term blue white to describe diamonds that exhibit blue ultraviolet fluorescence. About 30% off all diamonds will exhibit this characteristic. Though ultra-violet fluorescence is not visible to the naked eye, though its effect may be. Blue is the complement of yellow, meaning that blue fluorescence in diamond effectively cancels out some of the yellow in the diamond’s body color. As a result, fluorescent diamonds will face up whiter than their actual color grade might suggest–a fluorescent H might look like a D color. It is UV fluorescence is also responsible for the super-charged saturation of very fine Burma-type rubies.

The gem I examined, a 9+ carat D-Flawless took on a distinct distinct bluish glow in direct sunlight. I had never seen this before. The blue glow was distinct and visible. Unable to believe my eyes I re-examined the certificate, it read: “no fluorescence”! I checked the stone myself, there was absolutely no fluorescence in either short or long-wave UV. How could this be?

Ian Balfour in his book, Famous Diamonds specifically mentions a “light blue tinge” as a characteristic of The 140 carat Regent Diamond. The Regent, originally called “The Pitt” was brought to England in 1670 and is, unquestionably, of Golconda origin (above left). Diamond scholar Herbert Tillander describes this affect as a “blue afterglow.” and notes that most Type II diamonds do not fluoresce. One exception, the Hope Diamond, a Type IIb (contains Boron) will not only fluoresce it will actually phosphoresce meaning that the stone will continue to glow last after the UV light source has been removed. Tillander further notes that some Type II diamonds have been found in South Africa’s Premier Mine, other sources mention Brazil.

Blue Haze:

Not all Type IIa diamonds exhibit this characteristic though Golconda stones do. I was able to examine another D-Flawless type IIa that placed side by side with the 9 carat, failed to exhibit the blue glow. In the Golconda stone, in direct sunlight, the blue hue floated above the gem like an early morning haze.

Fine Crystal; The 4th C:

Perhaps due to their pure carbon composition, Golconda diamonds exhibit another characteristic, a high degree of transparency, Balfour describes The Regent as having a “unique limpidity” that some dealers refer to as “super-d” or what I refer to in my book Secrets Of The Gem Trade, as a super-crystal. Very fine gems of all colors possess this characteristic. Compare a regular wine glass with one made of lead crystal, hold both up to the light and you will get the idea. When compared to another D color Type IIa not of Golconda origin, the difference was unmistakable. The characteristic strikes one as a combination of ultra-limpidity coupled with what connoisseurs refer to as “whiter than white” both characteristics were visible in the Golconda but not in the other gem.

The stone I examined was cut in a fashion almost identical to the Regent, a cut known as a baroque brilliant or old European (image left). Stones cut in this fashion are of a different character than the modern brilliant. The crown is higher and the pavilion facets are shorter and broader.

A fine diamond possesses two characteristics that define its beauty, brilliance and dispersion. Dispersion is the ability to break white light up into its constituent rainbow colors. In the single minded pursuit of maximum light return, modern brilliant cut gems have sacrificed dispersion to produce maximum brilliance. As a result they have become soul-less light return machines. A well cut baroque brilliant by contrast will exhibit a balance of brilliance and dispersion that gives the diamond its distinct character and beauty–a character that is missing in so many modern super-ideal cuts.

(image above, side view of Golconda diamond), Compare the color of the center with the side trillion that is definitely not of Golconda origin.

To summarize, there appear to be three visual characteristics that define the beauty of Golconda diamonds: A high degree of limpidity (crystal), an ultra-whiteness and a blue afterglow that appears in natural daylight. Golconda gems are Type IIa diamonds and this can be established by scientific testing. All Type IIa diamonds, however, are not Golconda diamonds; to be considered Golconda, they must possess the visual characteristics just described.

It is unclear whether Type IIa diamonds from other sources possess the characteristics discussed above, there certainly are some that do not. However, in the final analysis, we are interested in gems not geography. in gems beauty is the ultimate criterion. When it comes to Golconda diamonds if they deliver the goods, how much does source really matter.

If you are interested in learning more about Golconda Diamonds or are simply looking for a new way to dazzle your friends at cocktail parties. Read more about the four Cs of connoisseurship. Follow me on gem buying adventures in the pearl farms of Tahiti. Visit the gem fields of Australia and Brazil. 120 carefully selected photographs showing examples of the highest quality gems to educate the eye, including the Rockefeller Sapphire and many more of the world’s most famous gems. Consider my book: Secrets Of The Gem Trade, The Connoisseur’s Guide To Precious Gemstones.

“Wise is a renowned author… He’s
done a marvelous job of this first book, monumental work, a tour de force…My recommendation: Buy this book”.

Charles Lewton-Brain, Orchid

Only $37.95. Read a couple of chapters online: www.secretsofthegemtrade.com.

Buy it on Amazon: www.amazon.com

“Secrets of the Gem Trade” subject of Ventfort Hall lecture

– July 30, 2007

Described by Gemkey Magazine as “one of the world’s foremost gem connoisseurs,” gemologist Richard W. Wise will bring his expertise to a Ventfort Hall Mansion and Gilded Age Museum visual presentation on Wednesday, August 29 at 4 p.m. A Victorian Tea will follow this final lecture of Ventfort Hall’s summer series.

Admission for the lecture and tea is $15 per person, members $12. For more information or reservations, please call 413-637-3206. Ventfort Hall is located at 104 Walker Street in Lenox.

The Golconda Diamond

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Golconda Diamond

by Richard W. Wise

Just the other day one of my readers emailed a question about Golconda diamonds. A search of the literature reveals a great deal of uncertainty about the exact meaning of the term. The source of some of the confusion can be traced to the fact that the term Golconda diamond, like many another bandied about by diamond dealers and auction houses has more than one definition; this one appears to have two; one geographic the other varietal.

Definition 1:

Until the year 1725, when diamonds were discovered in the Brazilian state of Minas Gerais, most of the world’s diamonds came from India. A group of mines concentrated around the Krishna River in the Kingdom of Golconda, located in the modern Indian state of Andhra Pradesh, were one major source of Indian diamonds. A majority of the diamonds mined were subsequently sold in the City of Golconda which became a major trading center. Several of the major mines, including Rammalakota and Kollur are mentioned by the famous Seventeenth Century French gem merchant Jean-Baptiste Tavernier as being a source of high quality diamonds.

Thus, our first definition: A Golconda diamond is a diamond from a specific geographic area within the historic Kingdom of Golconda.

Tavernier was one of the first connoisseurs to notice that diamonds from these mines were often exceptionally transparent and describes the best of the stones as” gems of the finest water.” The four criteria for evaluating any gemstone are: Color, Cut, Clarity and Crystal. These are what I refer to in my book, Secrets Of The Gem Trade, as “the Four Cs of Connoisseurship.” The term “water” combines two of the four, color and crystal. Color in diamond refers to relative colorlessness, a diamond graded “D” the highest grade, is a diamond totally without any trace of yellow. Crystal is the synonym for transparency that I have chosen to describe the fourth C of connoisseurship. I chose it because of its connotation (clear as crystal) and because it starts with the letter C and rhymes with the other three and is easily remembered.

Modern scientific analysis has shown that many famous high quality diamonds such as the Cullinan, Regent (image: at top of page) and The Koh-I-Noor that can be proven to come from the Golconda area are of a specific type of rare, almost pure diamond known as Type IIa. Less than 1% of the world’s diamonds are Type IIa. Scientifically speaking, Type IIa diamonds are diamonds that conduct electricity and contain no significant amount of nitrogen in the diamond crystal lattice.

Nitrogen is the impurity in diamond that imparts the yellowish hue. The lack of yellow makes for a pure colorless (D,E,F) color diamond. For some unknown reason, possibly plastic deformation of the crystal or unknown color centers, some type IIa diamond have yellowish, brownish or even pink body color. Some experts claim that all Golconda diamonds are Type IIa. There is, as far as I know, no scientific evidence to back up that claim.

Definition 2:

Science has not explained the exceptionally degree of transparency found in many Golconda stones. Some Type IIa diamonds also exhibit exceptional transparency or crystal. It may have something to do with the purity of the carbon crystal lattice. Type IIa diamonds are highly transparent in shortwave ultraviolet light.

The visible attribute is variously described as “clear as a mountain stream”, “whiter than white” and “super-d”. Some of these terms are misleading what we are talking about is super-crystal.

Transparency is more important in gems that are poorly cut. In India, then as now, good proportions took a backseat to size and weight. The French Blue, the type IIb gem that eventually became the Hope Diamond was originally 112 carats. Five years after Tavernier sold the stone to Louis XIV, Pitau the king’s diamond expert recut the stone to 66 carats to improve its brilliance and life a 40% loss in weight that would never have been countenenced in India. Visually, gems of fine water, however well cut, possess a unique beauty not found in other diamonds. In a world flooded with diamonds, this is indeed something special.

Thus, our second definition: Diamonds regardless of geographic origin that are of high color (D-E) that exhibit exceptional crystal are often called Golconda Diamonds.

The situation discussed above in not unique. Before gemologists worked out a way to identify the geographic origin of some diamond, ruby, sapphire and emerald; gems with characteristics similar to those from a certain source were often described using geographic terms such as Cape (as in Good Hope), Kashmir, Burma and Ceylon. These terms have become ingrained in the public mind and associated with certain levels of quality. So today gemstones that can be proven to come from a famous location will often command a high premium that has little or no relationship to the quality of the given gemstone. At auction, diamonds with a proven Golconda provenance may fetch a premium of 50% or more over a diamond of comparable quality that lacks the Golconda provenance.

How does one establish that a diamond is from Golconda? Well, if you can document a chain of ownership dating back to 18th Century India you have a good case. If you are depending on science, forgetaboutit. Even if all Golconda diamonds were type IIa, it does not follow that all IIa diamonds are from Golconda. In fact we know that Brazil has produced type IIa stones.

So, eventually, you think, science will solve the puzzle. Not likely, diamonds are formed within the earth’s mantle deep beneath the country rock where ruby, sapphire and emerald are formed. Diamonds do not contain the signature inclusions that can be matched up with specific geographic locations that make it possible to identify their origin.

Ok, so which would you rather have, a diamond with high color and exceptional crystal or a diamond from one of the historic mines of Golconda? Well, if you are selling the best answer is both because if it of the finest water and a proven Golconda provenance it will command the highest premium of all. Speaking for myself, give me the most beautiful rock. Wouldn’t it be a lot simpler if the finest diamonds came from Hoboken, New Jersey.

“Wise is a renowned author… He’s
done a marvelous job of this first book, monumental work, a tour de force…My recommendation: Buy this book”.

Charles Lewton-Brain, Orchid

Only $37.95. Read a couple of chapters online: www.secretsofthegemtrade.com.

Buy it on Amazon: www.amazon.com