Collecting and Classifying Colored Diamonds

3 COLLECTING: NATURAL COLOUR DIM\ONDS At some time or another, we have all had our curiosity excited and our interest piqued by an odd assortment of colourful bottles, iridescent shells, peculiar buttons, even old hat pins, marbles, or coins. For some it is a passing interest, but for others the interest grows into a passion for collecting (Muensterberger 1994; Rheims 1959).

The same curious enthusiasm can be said of collecting coloured diamonds. Whether old or newly faceted, faintly tinged or intensely coloured, these sparkling curiosities have emerged as one of the hottest and most eagerly sought after collectable items of the modern era (Figs. 3.1 through 3.3). "... The market tor fancy colour diamonds is truly an arena in which collectors do battle to possess these ultimately rare and spectacular objects ... the number of these stones available at any one time is so small, that statistics cannot be applied, and the price of every stone is as unique as the object in question. .. "

J.E. Arem

1982

FIGURE 3. 1. The scene at Sotheby's prior to bidding on a coloured diamond.

87

FIGURE 3.3. Once a year coloured diamond collectors and connoisseurs gather in Geneva to participate in the Argyle Tender - an invitation only event with sealed bidding - featuring a limited selection of natural pink diamonds recovered from the Argyle diamond mine located in NorthWestern Australia.

(Argyle 1984 & 1988; Harris 1991; Hofer 1985; Rayner 1996)

FIGURE 3.2. A coloured diamond being offered for sale at Christie 's.

What is it about coloured diamonds that has so captured our attention? Perhaps it is the strangeness of a particular colour, such as the vivid teal blue sold at Sotheby's in New York on April 14, 1994 (Lot 433) (Fig. 3.4), or the antiquity of the magnificent Edwardian brooch that featured two pear-shaped diamonds of a pure blue hue that sold at Christie's in New York on October 21, 1992 (Lot 591) (Fig. 3.5). For others it may be the surprise of discovering an unknown bit of information about a stone, such as the excitement of finding out that a polished coloured diamond with an older (antique) cut appears to have a stronger body colour when removed from its original mounting, making it a perfect candidate for recutting. Or perhaps our fascination comes from the sheer, compelling beauty of a well -made fancy coloured diamond or from the intrinsic value placed upon a fancy intense coloured diamond.

FIGURE 3.5. An Edwardian brooch with two fancy blue diamonds weighing 2.66 carats and 2.98 carats.

FIGURE 3.4. An unusual teal blue diamond weighing 0.41 carats.

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Some collectors are captivated by the historical accounts of famous coloured diamonds, as well as the exploits and misfortunes of the people who once owned them, i.e., the history of origin and ownership -

what people in the trade call

the diamond's "provenance" (Federman Oct 1988). This admiration for coloured diamonds stretches far back in time beginning with the most famous coloured diamond - the Hope . This blue diamond was originally known as the Tavernier Blue after Jean-Baptiste Tavernier, an extraordinary diamond merchant who was the first to describe it (Tavernier 1676). In fact, many coloured diamond collectors consider themselves the modern-day equivalent of Tavernier, logging many miles around the globe in search of interesting and unusual coloured diamonds. Tavernier on the other hand, did not enjoy the luxury of modern travel, yet his exploits through Turkey, Persia, and India are legendary in the diamond business (Ball 1889; Joret 1886; Zara 1976).

For example, during his last voyage to India (March 1666 through December 1668) historians believe he purchased the Tavernier Blue, a rather large (1 15.28-carat) dark blue Indian-cut diamond which he then sold in 1669 to King Louis XIV (Morel 1988; Patch 1976). This gem was eventually recut in 1673 by Pitau , the court jeweler, into a 69-carat triangular-shaped stone known as the Diamant Blue or French Blue diamond. Years later, it was stolen during the French Revolution (1792)

and subsequently recut into what gem historians believe to be the 45.52-carat cushion-shaped Hope diamond (Morel 1988; Tillander 1975).

There are many other stories linking coloured diamonds with famous and intriguing people, and such tales excite and entice collectors. For example, there is a black and white photograph of a magnificent eighteenth-century cluster-style necklace, with matching brooch and earrings, composed of fancy colour diamonds shown in George Blakey's book, The Diamond (1977, p. 201 ). This ensemble was presumably part of the ransom offered to the Sultan of Turkey by Empress Catherine of Russia following the capture of her husband, Peter the Great, at the Battle of the Pruth in 1711 . Also, Babur (1483 - 1530), the founder of the Mogul dynasty, was once the proud owner of the legendary 32.24-carat Agra pink diamond , which was recently sold at auction (Christie's LD Jun 1990 Lot 232), and later recut into a 28.15-carat rectangle-octagon (shape) modified brilliant (cut) stone (J. Leffler, pers. comm., 1990).

This brings up an interesting point concerning the commercial provenance (i.e., historical value) of notable (famous) coloured diamonds. Namely, that the historical value attached to any so-called "famous" coloured diamond applies only if the stone remains in its original form (i.e., shape, cut, and carat weight). However, if the cutter records the transition of the stone during recutting (or if the body colour is so unique that it can be traced to the original, e.g., the Hope), the provenance of the diamond can continue. According to the opinions of many collectors, once a stone like the Agra is recut it loses the original identity for which it was famous and it now becomes a different stone, hence it will lose its historical value with this new identity.

According to the opinions of many dealers, the loss of historical value by the act of recutting a famous coloured diamond is negated by the improvement in the stone's

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face-up colour. In other words, if recutting dramatically improves the face-up appearance (i .e., apparent colour), this increase in apparent value can often outweigh the loss of historical value . Clearly, many collectors are in favor of keeping historically important coloured diamonds in their original forms, whereas many dealers and cutters favor recutting such stones (especially if the inherent body colour is pale) in an attempt to improve their colour grade.

Other collectors are excited by the possibility of owning a specimen that was once part of a famous collection, such as the coloured diamonds from the Duke of Brunswick's collection auctioned in Geneva on April 22, 187 4. This collection contained a treasure of coloured diamonds appropriately described in the catalogue as rose, apricot, china red, ink blue, and jonquil to name a few. Another interesting sale of coloured diamonds occurred in Paris on June 24, 1909 from the estate of Salomon Habib (Habib 1909; Sinkankas 1991, No. 2641 ). The Habib Collection, as it is referred to, contained only eight stones yet each was notable for its colour and/ or size. Of particular importance to the collector, the famous Hope diamond was listed under item number eight in this sale, yet it went unsold for a variety of reasons relating to the prevailing economic conditions (Morel 1988).

Another interesting sale occurred in Paris on November 29, 1911, referred to as the (Sultan) Abdul -Hamid II Collection (Abdul 1911; Sinkankas 1991, No. 6). Very often the Habib sale (1909) and the Abdul-Hamid sale (1911) are confused with each other. The Abdul-Hamid sale is notable for a large cushion -shaped yellow diamond (Lot 309), which was once a part of the treasures belonging to the Turkish Sultanate. It is believed that this stone Hamid II catalogue -

and the other items in the Abdul-

was confiscated from the famous Yildiz Palace at Constantinople

(now part of lnstanbul) by members of the Young Turk Ministry on , or shortly before, April 27, 1909, following the Sultan's deposition and eventual exile. Many years later this same stone (73.93 carat) was resold at auction; at that time it was described FIGURE 3. 6. A Georgianstyle brooch featuring several natural pink diamonds weighing from 0. 68 carats to 3. 18 carats.

(graded) as a fancy light yel low (Christie's NY Apr 1981 Lot 285) . More recently, the Henry Sherek collection of coloured diamonds (assembled under the guidance of Eduard Gubelin) was offered at public auction (Christie's GN Nov 1987 Lot 731) among other collections (e.g., Christie's GN Nov 1976 Lot 368 & GN Nov 1994 Lot 378 and Sotheby's GN Nov 1995 Lot 269) .

Sometimes col lectors are drawn to a single, older piece of jewelry, such as an exquisite brooch -

offered at Sotheby's New York, on October 27 , 1981

(Lot 180) that featured several "old mine cut" pastel pink diamonds -

which was so

finely preserved that it assumed the status of a collector's gem (Fig . 3.6) Or perhaps what captures our attention is merely the glittering beauty of absolute perfection . This perfection is found, for instance, in the 14-carat fancy intense yellow marquise of natural colour (Fig. 3.7). a precisely cut and internally flawless diamond that was auctioned at Sotheby's in St. Moritz on February 20, 1988 (Lot 837).

FIGURE 3. 7. A magnificent 14-carat yellow diamond.

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No matter what circumstances introduced the collector to a particular coloured diamond, there is a quick realization that he or she is in possession of one

of nature 's masterpieces. As a collector begins to develop a familiarity and aesthetic appreciation for what is available in the market. he or she soon discovers that others have had the same interest. Connoisseurs such as Shah Jahan (d. 1666), King Louis XIV (d. 1715), Frederick Augustus II (d. 1763), Sir Abraham Hume (d. 1838), Henry Philip Hope (d . 1839), Virgil von Helmreichen (d. 1852), Duke of Brunswick (d. 1873), Sultan Aji Moehamad Soelaiman XVII (d. 1899), Sultan Abdul Hamid II (d. 1918), Gardner Williams (d. 1922), Atanik Eknayan (d. 1925), Louis Winans (d . 1926), Maharajah of Nawangar (d. 1933), Lincoln Ellsworth (d. 1951 ), Salomon Habib (d. 1961 ), Nizam of Hyderabad (d . 1967), Warren Hancock (d. 1981 ), and Andre Gumuchian (d. 1984) are indelibly remembered for the coloured diamonds they collected .

"... The Sultan, I found, ... has, in fact, a mania for collecting all kinds of miscellaneous objects, .. . Jewellery generally, and especially diamonds, are his passion. Of the latter he has a splendid collection, whether for the number of specimens it contains, or for the size and variety of the stones, which range from the purest water to yellow, green, and grey-blue, or black. The whole of these diamonds were found in Borneo .... The Sultan is in a perpetual state of negotiation with merchants and others for the purchase of diamonds, and his passion for them has more than once involved him in difficulties. "

C. Bock

1881

Collecting coloured diamonds is not only a process of acquiring and possessing. Most importantly, it is a process of selecting exemplary specimens that appeal to an individual's own sense of taste and beauty. In many ways, the most intrepid collectors of coloured diamonds are the ones who pursue the art according to their own vision , not the established attitudes of the market. It is these avant-garde experiments -

which usually take place in private salons or at public auctions whereby

collectors purchase unique and rare colours at often record prices -

that ultimately

hone a collector's taste and interest. The appeal of collecting is based on more than just the thrill of personal satisfaction or possession of a rare mineral treasure. Sometimes the diamonds that appeal to collectors provoke a deep fascination, prompting new owners to refer to them as "their babies," as if the stone was now part of the collector's family (E. Elzas, see Shor 1981; L. Asscher, see Wilson 1972). Collectors have also told me on various occasions that seeing a fine (beautiful and rare) coloured diamond is like looking into the eyes of a dear friend or relative: there is an instant and positive personal connection between the two (A. Bronstein, pers. comm., 1995).

"... you look at jewels just as we look at faces. You recognize them immediately for what they are, as we recognize people for who they are .. . If you are like me, you look at stones with an eye that sees right into them."

Harry Winston

1970

(see Wilson 1972)

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As is often the case with coloured diamond collectors, many of them specialize, becoming totally preoccupied with collecting exquisitely beautiful specimens of well-known colours, such as (lemon) yellow, (rose) pink and (sky) blue (Fig .

3.8), or obscure colours, such as (tobacco) brown and (lilac) purple (Fig. 3.9). Other specialized collectors procure diamonds of fascinating hybrid colours that remind us

of the delicate colours found in nature, such as (pumpkin) yellow-orange, or colours inspired by man, such as (cognac) yellowish brown-orange (Fig. 3.10). Others focus their attention on unusual colours that seem sombre or unnatural to the inexperienced observer, such as (cadet) gray or (sage) olive (Fig . 3.11 ). There are even collectors who by virtue of their knowledge of how light reflects inside a polished diamond, prefer to collect odd shapes and intricate cutting styles that affect the face-up colour in ways that remind us of abstract art (Fig. 3.12). Virtually anyone who has the instincts for collecting and appreciating beauty, colour, the art of diamond cutting, crystalline perfection, and the rarity of natural objects of any kind can feel perfectly at home with and highly intrigued by coloured diamonds. Without a doubt, because of nature's infinite diversity and seemingly inexhaustible supply, collectors can be kept forever occupied in locating and acquiring exciting additions to their collections.

FIGURE 3. 8. A platinum brooch featuring lemon yellow, rose pink, and sky blue diamonds. (Sotheby's NY Apr 1991 Lot 305).

FIGURE 3.9. Aurora No. 123, a pure brown (BR), and No. 201, a pinkish purple (pk-PP), next to a colourless diamond.

FIGURE 3. 10. Aurora No. 43, a yellow-orange (Y-0), and No. 81, a yellowish brown-orange (y-BR-0), next to a colourless diamond.

FIGURE 3. 11 . Aurora No. 1 76, a bluish gray (bGY), and No. 166, a grayolive (GY-OL), next to a colourless diamond.

FIGURE 3.12. Aurora No. 74 a pure yellow (Y) diamond, and an abstract painting by Howard Hofer. Certain facet designs such as the rectangle-octagon (shape) modified brilliant (cut) and others, create unusual and artistic patterns of coloured facets in the face-up.

These specialized coloured diamond collectors also focus their attentions and finances on acquiring stones of, for instance, a particular colour variety (e.g., pinks), similar colour tones (e.g., intense), similar size and/or shape (e.g.,

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half-carat rounds), different colours with the same shape (e.g., pears), or colours and characteristics from a particular geologic locality (e.g., Australian bubble-gum pinks or South African cape yellows). Such groupings are often referred to as mini-collections . These small gatherings of stones, while not exemplifying the qualities of a bona fide collection, do provide their owners with the same sense of pride and satisfaction shared by all collectors. In many instances , these accumulations or mini-collections find their way into an exquisite piece of jewelry, whereby their specific shapes and contrasting colours provide a perfect ensemble for a brooch (Fig. 3.13) , or possibly a bracelet (Fig . 3.14).

FIGURE 3.13. A modern brooch containing pear shapes of assorted colours. (Sotheby's NY Apr 1991 Lot 287)

FIGURE 3. 14. Two bracelets containing round diamonds of assorted colours. (Christie's GN Nov 1990 Lot 450)

In addition to these, there are specialized collections that feature matching colours or colour gradations within a single hue; these are usually collected for purposes involving jewelry. Such an ensemble of tiny Australian pink diamonds and a larger Brazilian pink diamond of similar colour was featured in a necklace auctioned at Christie 's in Geneva on May 21 , 1992, Lot 427 (Fig. 3.15).

This exquisitely colour-coordinated diamond mini-collection is a true testament to the collector's art and a fine example of specialized diamond collecting. The matching pink diamonds were patiently assembled by Ralph Esmerian, a notable connoisseur of coloured diamonds. (See

a/so Christie's NY Oct. 1996 Lot 543; Ward 1993, pp. 40-41.)

By contrast, the Aurora Collection is referred to as a systematic collection . A systematic collector has added to his collection when he can, one or more examples

FIGURE 3. 15. A necklace containing 146 Australian pink diamonds and a larger Brazilian pear-shaped diamond of similar colour

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93

of diamonds that are new and distinct colours , which include examples representative of all the colour varieties known to exist in diamonds, including various subvarieties (e.g., see Bronstein 1995; Brunswick 1874; Crespin 1984; Diamond News 1980; Eknayan 1904). As far as I know, there is no privately held mineral , insect. shell , or plant collection in the world that contains a// the specimens known to man. The same is true for systematic collections of coloured diamonds , which presents a strong challenge to the collector who wants an outstanding collection of completeness .

First of all, the ability to distinguish one colour variety from another is a study unto itself. When you add to this the large number of colour mixtures , or colour modifiers, that are known to occur in coloured diamonds and the incalculable colour patterns they exhibit in the face-up, you have a long-term study that can be pursued by eye with no scientific knowledge, or it can absorb the total mental activities of a collector, a research gemologist , and a colour scientist. The collectors who pursue their art solely by eye probably have the most fun ; however, since colour memory is not a well-developed sense, they are prone to subjective colour errors that can result in the purchase of duplicate colours for their collection.

It is my observation that many astute collectors and connoisseurs have trained themselves to recognize by sight subtle colour differences in a wide array of colours . In the process of developing this skill , a collector uses visual comparisons with other coloured diamonds to bolster his or her own opinion. In many instances, the subtleties of a coloured diamond only present themselves to our eyes when we contrast and compare them against one another (see chapter 9). It is a fascinating and intriguing experience to watch two or three connoisseurs looking over a selection of coloured diamonds. With little disagreement and without hesitation , all will point to the same specimen as being the "best" without ever having seen the stones before. They have learned and are applying an unspoken and unwritten set of criteria that all collectors grasp through experience and trial and error. Coloured diamond connoisseurs refer to this knack for picking exemplary colours as fein schmecker (German for "having a taste for fine things"), which liberally translates into

"a gourmet of colour" or in slang "having a nose for colour."

To become a knowledgeable collector of coloured diamonds and then an astute connoisseur, one must devote time and patience to the art of judging beauty over a wide variety of colours, not just the commercially popular colours. The dictionary defines a connoisseur as "a person aesthetically versed in any subject. .. an expert competent to act as a critical judge of the arts, or in matters of aesthetic taste." Thus it is quite possible that any amateur collector can work toward becoming a connoisseur of coloured diamonds , if he or she develops a strong interest.

Eventually, as budgets allow and perseverance enables them to search out new specimens, a collection becomes filled with diamonds of extraordinary beauty, quality, and rarity, and ultimately monetary value.

One thing common to all the great connoisseurs and builders of great collections is a high aesthetic sense. This is an elusive and difficult quality to define, but whoever has it is able to compare coloured diamond specimens and select the

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best among them. Regrettably some would -be collectors never develop this sense, while others suddenly discover they have always had it and can apply it with ease.

Even with an aesthetic sense, selecting the best coloured diamond for a collection is really a matter of making a judgment of its beauty and rarity based on comparison with like specimens.

Thus for the collector of coloured diamonds such decisions are better made if one has already seen and compared many specimens over several years time. As things stand , the only sure way of judging coloured diamonds is through the experience of speaking with those who know these stones and by examining private collections. You may also wish to speak directly with diamond dealers or retail jewelers who are well versed in coloured diamonds. And a wealth of information is available to the collector who visits public auctions of gemstones or any one of the museums around the world that feature coloured diamonds on public display.

In 1904 for example, many lovers of gems and members of the diamond trade gathered at the St. Louis Exposition to view the collection of coloured diamonds exhibited by Atanik Eknayan , a diamond cutter from Paris. The display, which was said to be one of the largest and most valuable displays of rare unset jewels offered for public inspection, provided the novice and the expert with a unique glimpse into the rarefied world of coloured diamonds. "Mr. Eknayan's booth , as will be seen from the illustration, is very simple, measuring 8x8 ft . between the railings , just large enough to hold the trays, or white velvet plaques , on which these gems were inset for inspection . Although all are diamonds, the colors they display include every tint of the rainbow, over 70 distinct shades being included" (Eknayan 1904).

From May 1976 through June 1986, coloured diamond enthusiasts regularly visited the 41 -stone Gumuchian Collection of coloured diamonds on display at the American Museum of Natural History (AMNH) in New York (Hofer 1981 , fig . 1; Keller G&G 1976su, photo insert; Zucker 1984, fig. 108). In 1981, the 301-stone Rainbow Collection visited the AMNH for a brief exhibit; followed by brief exhibits in 1982 at the Museum of Natural History in Los Angeles, 1983 at the Academy of Science in San Francisco, and 1984 at the Antique Dealers and Jewelers Biennial Fair in Paris. It is widely believed in the diamond trade that both of these collections no longer exist , or do not exist in their original forms .

Today, there are few coloured diamond collections on permanent public display other than the Aurora Collection. The DeBeers Collection, which features an interesting assortment of colours from various diamond mines (Copeland 1974, p.76a), has been displayed at various diamond industry functions over the years.

Recently, the Houston Museum of Science exhibited a unique collection of fancy colour diamonds referred to as the "Butterfly Collection," which was on temporary loan from July 1994 through January 1996. The Townshend Collection in the Victoria and Albert Museum , London , contains eight small diamonds of various colours (Church 1913; Westropp 1874). Thus, persons interested in observing these unusual collectable items up close have to settle for public displays of one or two coloured diamonds rather than an entire collection (Table 3.1 ).

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For example, the National Museum of Natural History (Smithsonian Institution) in Washington D.C. has the 67.89-carat Victoria-Transvaal diamond of champagne brown colour, the 45 .52 -carat sapphire blue Hope diamond, the 30.82carat steel blue Unzue diamond (Balfour 1987) also known as the Couer (Morel 1988), often incorrectly referred to as the Eugenie blue diamond (Ayer 1971; Nadelhoffer 1984), the 5.03-carat OeYoung garnet red diamond , the 18.30-carat Shepard canary yellow diamond and the 2.90-carat De Young rose pink diamond on display; the Green Vaults (Grunes Gewblbe) in Dresden , Germany, house the 40-plus-carat Dresden apple green diamond ; the Conde Museum in Chantilly, France, owns the

9.01-carat Conde rose pink; the Apollo Gallery (Galerie d 'Appollon) of the Louvre in Paris exhibits the 21 .32-carat Hortense peach pink; the Kimberley Mine Museum in Kimberley, South Africa, exhibits the 10.73-carat Eureka cape yellow; and the Residence Museum (Residenz Schatzkammer) in Munich, Germany, houses a suite of pink, blue and yellow diamonds mounted in the Order of the Golden Fleece (Legrand 1980; H. Tillander, pers. comm., 1996; Twining 1960).

TABLE 3.1.

Coloured Diamonds on Public Exhibit Weight

Name

Colour

Location

128.51

Tiffany

Yellow

Tiffany & Company, New York City

67.89

Victoria-Transvaal

Brown

Smithsonian Institution, Washington

DC

usA

45.52

Hope

Blue

Smithsonian Institution , Washington

DC

usA

41.00

Dresden

Green

Albertinum Museum , Dresden Germany

38.00

Dresden

Yellow

Albertinum Museum , Dresden Germany

30.82

Unzue

Blue

Smithsonian Institution, Washington

DC

usA

22.00

Unnamed

Yellow

Smithsonian Institution, Washington

DC

usA

21.32

Hortensia

Pink

18.30

Shepard

Yellow

DC

usA

13.35

Paul I

Pink

12.00

Unnamed

Yellow

Smithsonian Institution , Washington

10.73

Eureka

Yellow

Kimberley Mine Museum, Kimberley S Africa

10.00

Penthievre

Yellow

Conde Museum, Chantilly France

9.75

Unnamed

Yellow

Natural History Museum, Paris France

9.01

Conde

Pink

9.00

Unnamed

Black

Smithsonian Institution, Washington

DC

usA

5.03

De Young

Red-Brown

Smithsonian Institution , Washington

DC

usA

2.90

De Young

Pink

Smithsonian Institution, Washington

DC

usA

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NY

usA

Louvre Museum , Paris France Smithsonian Institution, Washington

State Museums of the Kremlin , Moscow Russia DC

usA

Conde Museum , Chantilly France

There are several other references in the literature which describe coloured diamonds belonging to various museums or private owners (Balfour 1992; Copeland 1974); however, many have been sold, traded , or are not on exhibit. For example, the Topkapi Museum in Istanbul is reported to be in possession of a rare purple diamond mounted in a ring (Schubnel 1973); the Museum of Natural History (Naturhistorisches Museum) in Vienna reportedly has a collection of rough coloured diamonds gathered from Brazil by Helmreichen (Bauer 1904); and the Field Museum of Natural History in Chicago is said to own a "fine red diamond of 3/8 carat" (Kunz 1926).

Collecting fancy colour diamonds is no easy task. It requires knowledge as we have discussed, but it also requires patience and good luck. For example , a diamond cutter who regularly cuts colourless diamonds for a living is often reluctant to sell a coloured diamond right away. In his reasoning, if he handles thousands of carats of colourless and near colourless diamonds in a year's time, and only one is a deep yellow, pink, or blue, it then becomes difficult for him to part with it. Although there is a strong financial interest at stake, the cutter may have a stronger emotional attachment to the stone. It might be the only one he gets in his life , so the collector needs patience. One day the cutter may lose his attachment or just need the money from its sale. This is when the collector needs the good fortune of being in the right place at the right time . If you follow every lead , eventually you find the opportunity to buy a gem . That is when a collector needs the knowledge to know how rare and unusual a stone is and, of course, be prepared to offer fair value for it.

Value should be relative to the beauty and rarity. This is the challenge of collecting fancy colour diamonds.

"... surely no pleasure can be more innocent and justifiable than that inspired by the possession of beautiful natural objects ... " G.F Kunz

1913

"... Gems in their appeal are like stars. They enchant the eye, they stir the imagination.

Then, as with cats and clocks, they are 'company' ... " H.B. Bridgman

1816

"... A colored diamond is a touchstone of the universe, a little something God created that man can't always find. .. they are the last frontier of collectables ... " R. Winston

1986

(see Kaye 1986)

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4 MRITY: NATUML SUPPLY AND HUMAN DEMAND Now that we have explored the Aurora Collection of diamonds by viewing their colours, sizes, shapes and weights , let us move on to a very important aspect of collecting coloured diamonds -

rarity. For this we must go beyond just looking at

colours; we must begin to understand and organize what we see.

Visitors to the American Museum of Natural History are impressed to see that the Aurora Collection has so many specimens, with such a diverse range of colours (Fig. 4.1). Almost every colour seems to be represented. Of course, this is what collectors do. They do not simply assemble large quantities of gemstones, or stamps or old automobiles or furniture; instead they develop a plan for their collection and then pursue it according to this plan. The Aurora Collection is limited to diamonds, specifically coloured diamonds , and within this elegant subdivision of the universe of gemstones are examples of the extensive range of colours in which diamonds occur. And while it is true that all coloured diamonds are rare natural occurrences, there are differences in rarity among different colors; certain colours are more or less rare than others .

FIGURE 4. 1. A suite of coloured diamonds {left to right) grayish green (Aurora No. 1), purple-pink (Aurora No. 9), brownish yellow (Aurora No. 3), pure blue (Aurora No. 7), pinkish purple (Aurora No. 2), and yelloworange (Aurora No. 25).

99

Every collector knows, no matter what the nature of the items collected, that it soon becomes necessary to organize the different specimens into a coherent arrangement, if only to be able to find what you wish without viewing the complete collection. Organizing a diamond collection by weight and dimensions is a simple process involving measurement alone; organizing diamond colour is more complex, involving colour measurement and subsequent interpretation of the data; and organizing coloured diamonds by rarity is even more difficult. Before we begin our discussion on rarity, let us look at what others have written about coloured diamond rarity.

The precious crystals of the Vaal river "... Extremely Rare Fancy Green Cushion-Cut Diamond."

Christie's (Oct 1988)

beds are exceptionally good and free from

"... A Collection of Rare, Fancy Color Diamonds."

Christie's (Oct 1989)

yellow. .. but there was a large percentag_e of

"... A Rare Unmounted Circular-Cut Chameleon Diamond."

Christie's (May 1990)

as to defy any scrutiny except that of experts.

" Extremely Rare Unmounted Circular-Cut Fancy Bluish Green Diamond."

Christie's (Oct 1992)

fractures ... some were lightly tinged with stones perfectly white or so nearly colourless

Deep orange yellow stones were occasionally found, and shades of yellow grading into the finest straw colour were represented as well as pale blue, brown, pink, and other hues; but

any colour except white [i.e. , colourless] or "... A Very Rare Fancy Brownish-Purple Diamond."

Habsburg, Feldman (Oct 1990)

yellow was rarely to be seen. " G.F Williams

"... Rare Fancy Intense Yellow Diamond Lavaliere."

Sotheby's (Oct 1987)

1905

"... No adequate figures exist as to how rare

"... A Rare Unmounted Fancy Pastel Linden Green Diamond."

Sotheby's (Feb 1989)

fancies are. I am inclined to believe, however,

"... Rare Fancy Dark Blue Diamond."

Sotheby's

wholly unsuitable for gems, that fancies make

that of the total world's diamond production to date, including of course much material

(Apr 1993)

"... Extremely Rare Fancy Colored Diamond Ring."

Sotheby's (Apr 1994)

up but about 111OOth of a percent of the total.

Of unusually fine cut material, one stone in from 2500 to 5000 may be a fancy" S.H. Ball

1935

".. . Mention has been made in the literature of a blood-red diamond, but we ourselves have never encountered this colour in diamond crystals, despite having examined vast numbers of stones; neither have any other workers [researcher] described red diamonds. It seems evident that this colouration of diamond is exceptionally rare."

YL. Orlov

1977

"... Rarity may be responsible for the status of coloured diamonds, for each natural fancy coloured diamond there are at least 10, 000 colourless diamonds. "

E. Fritsch

1991

(see Athineos 1991)

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As you can see, many authors, lecturers, and diamond industry professionals have approached the subject of rarity in coloured diamonds before me, expressing their views on the subject. However, it is intriguing to note, when you decipher what each has to say, that each writer or lecturer only presents one-half of the rarity picture, never the whole picture. Nevertheless it is very important for the collector to grasp both sides of the rarity question , before he or she begins the pursuit of building a collection of rare specimens.

Rarity refers to items "infrequently found, seen, or experienced -

Rarity

as in a rare event , or a rare species" (The New Lexicon: Webster's Dictionary).

Whatever your definition is for rarity, it must include the operative word infrequent a synonym for rarity. When referring to coloured diamond rarity, there are two different aspects of rarity, together they form the complete picture of rarity in diamond. I call these two types of rarity - true rarity and false rarity.

True rarity in natural coloured diamonds refers to the rarity imposed by nature: How many of a certain colour (according to the physical laws of science) did nature produce? False rarity in natural coloured diamonds refers to the rarity imposed by man: What is the commercial desirability of a certain colour over another?

This is usually established by a consensus of opinions by individuals engaged in a similar activity such as buyers and sellers. For instance, I have often overheard diamond merchants remark, "It is definitely a rare diamond -

it is the best yellow I have

ever seen ." Therefore, based on their experiences they are giving it a false (perceived) rarity. I find rarity to be a fascinating subject. It pits true (natural) rarity, involving aspects of physical science and the diamond researchers who discover how and why a diamond acquires its colour -

against false (man-made) rarity, involving the desire

for dealers and collectors to possess that which is deemed rare by the marketplace.

As a coloured diamond consultant, I am often asked , "Is this diamond rare?" In almost 100 percent of those cases, the person is really asking , "Is this diamond commercially desirable?" This inquiry is about a false rarity, which refers to the established hierarchy of colours that are considered commercially desirable according to market (changeable) conditions and personal (subjective) preferences for certain colours (Rubin 1995). As a collector delves into the subject of coloured diamonds, he or she eventually comes to know of this unwritten scale of false rarity, which is passed on by word of mouth from dealer to dealer or dealer to jeweler. However, on those occasions where a collector listens to a diamond researcher regarding an unusual colour-causing phenomenon (or reads the technical details in a scientific journal), the collector is getting closer to discovering true rarity in a coloured diamond.

True rarity thus refers to the actual (physical) infrequency of nature's ability to produce diamonds of certain colours, which can be organized according to scientific (objective) principles.

Ten years ago, before I was aware of what I just told you, before I put true rarity and false rarity into proper perspective, I used to think that people were asking about true rarity, when they asked if a stone was rare. That is, because my academic background only allowed me to see this one-half of the rarity puzzle, I wasn't

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thinking of a false rarity at that time; it just didn 't click yet. So in those days, I would take the time to explain true (physical) rarity of a particular colour for a client.

In a typical example, I might have said that an intense canary yellow colour is caused by nature's addition of nitrogen atoms to a diamond. But not just any nitrogen atoms, these are isolated (hermit) nitrogen atoms, meaning that they randomly take the place of individual carbon atoms in the diamond lattice, yet they don 't like other nitrogen atoms as neighbors, only carbon atoms, referred to as isolated substitutional nitrogen atoms (or type lb) by diamond researchers (Collins 1980 & 1982; DuPreez 1965).

Even if nature were generous enough to endow a diamond with a sufficient quantity of these isolated nitrogen atoms (approximately 100 nitrogen atoms per 1,000,000 carbon atoms), the stone would still have to undergo an arduous volcanic ascent where temperatures could exceed 1400 degrees Celsius. At these temperatures nitrogen atoms are so agitated that they begin to move around inside the crystal forming groups (nitrogen aggregates), which alters the colour from (type lb) canary yellow to the more familiar (type la) cape yellow, associated with the bulk of diamonds from South Africa (Fig. 4.2).

FIGURE 4.2. (Left to right) A pure yellow type la diamond (Aurora No. 234), pure yellow type lb (Aurora No. 105), and a pure yellow type la (Aurora No. 252) with a colourless diamond.

However, if a nitrogen-containing diamond does not endure temperatures above approximately 1300 degrees Celsius the nitrogen atoms will remain isolated (Chrenko 1977; Davies 1977 & 1981; Evans 1981 & 1982; Harris 1979; Woods 1986), enabling them to absorb light at wavelengths different than the cape yellow stones, resulting in a more saturated yellow body colour (along with other unique physical and optical properties), referred to as a canary yellow diamond (Anderson 1943; Collins 1980; Davies 1980).

The point of this lengthy description is , that a unique set of physical and chemical circumstances defines true rarity for a particular colour. The physical characteristics that cause colours in diamonds occur infrequently in nature, which is why coloured diamonds are rare in general and why certain colours are found more infrequently than others. The reason we do not see very many of the so-called canary colours in the market is because they require a special set of events to occur in

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the earth, whereas cape yellow colours represent geologic conditions that occur with greater frequency, and are therefore less rare in the true sense.

"... the history of our planet gives only a broad outline of the complicated processes that took place in the evolution of minerals and rocks . So many favorable circumstances must fortuitously concur if gemstones are to be formed that it seems

a miracle, or a benevolent disposition, that these complicated chemical and physical prerequisites occurred even once. That in fact deposits can be formed in several regions of the earth seems more than miraculous. But they remain rare accidents, and the rarity of gemstones is therefore the result of the enormous complexity and incredible coincidence of their formation. "

E. J. Gubelin

19 74

It is the same story for any of the other colours. Pick a colour; they all have a story of how they got their colour. Take green diamonds for example . Incidentally, when you speak of true rarity for a particular colour of diamond, you must learn to be specific and refer to the exact colour, such as yellowish green, bluish green , or pure green, etc. Thus when I talk about green diamonds, it is implied that I am speaking of 'pure' green diamonds, those that have no secondary colour modifiers.

This is very important to keep in mind as you begin to see how diamonds can be organized according to their true and false rarities. In this way, you will be comparing diamond rarity in a proper way, what people often refer to as "apples to apples," as opposed to comparing "apples and bulldozers."

In discussing the true rarity of pure green diamonds, I will summarize the process because the subject of green colour in diamonds, while fascinating, is very technical , and such a discussion is outside the scope of this book.

In a perfect world , a pure green diamond would begin its journey as an absolutely colourless diamond crystal deep in the earth. Such a colourless pebble is relatively impurity free (type Ila according to researchers), or it may contain a few impurities that do not affect absorption of light in the visible spectral region (type la), rendering them colourless also. After volcanic action transports such a colourless crystal up to the earth's surface, it resides temporarily (unless man finds it) in what is known as a primary diamond deposit (ancient volcanic pipe). At this stage a rough diamond crystal could acquire a natural pure green colour - the result of close proximity with a grain of radioactive ore -

however, this would be a superficial green colour.

When cut into a gemstone these green-skinned crystals end up as colourless gems.

"... Many of the diamonds have a thick dark grass-green skin, some spotted also with black, that they seem all.foul, yet not so, but within purely white and clean. ... " Earl Marshall of England

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103

But what about the pure green diamonds with so-called bottle green body colours, that the collectors and connoisseurs of the world identify as exceptionally rare? How do these stones acquire their colour? In order for a diamond to

acquire a uniform green body colour, it must first undergo the vicissitudes of erosion.

Over millions or billions of years it will be subject to the mechanical agents of erosion (wind, rain, gravity, etc.), which will eventually wash the diamond in a downhill direction as the water searches for the path of least resistance. Along the way, these river (alluvial) stones, if they contain stress or cracks within, will undergo the fatal misfortune of eventually being pulverized into dust. Yet, the lucky few that pass this test of abrasion, find themselves dropped from the water currents as soon as the gradient (slope) decreases -

as the water's velocity drops so does its ability to support and

transport diamonds. In these gravel-laden sedimentary areas known as sand bars, alluvium, terraces, and deltas, the diamonds (and other heavy materials including gold and various uranium oxide ores) accumulate over geologic time. At this point our colourless (or lightly spotted) diamond crystal is buried along with the gold and ore as sediments accumulate.

As the uranium rich ore breaks apart under the waters' assault, minute grains of uranium-rich sand come in direct contact with the diamond , causing what are known as alluvial green spotted diamond crystals. These alluvial (river bed) green stones were first encountered sporadically in the rivers flowing toward the towns of Banjarmasin and Martapura in South Kalimantan and the town of Pontianak in West Kalimantan (Borneo) in the sixteenth century, and in the ancient river beds of the Anantapur (or Golconda) district, Andhra Pradesh, India, in the seventeenth century. These green spotted crystals also occurred along watercourses of various rivers that cut across a group of Precambrian age rocks (more than 2.5 billion years old) in South America, known as the Brazilian shield. They also occur with great regularity in Africa, in such areas as the Vaal river basin in Southern Africa and in the Central African Republic along the Ubangi river.

As colourless diamond crystals lie buried next to uranium-rich ore over geologic time spans, a physical reaction takes place between the uranium and the diamond crystal. At every point where a grain of ore is in direct contact with the crystal (or in the case of a uranium-rich solution of mud that might surround the diamond), there is energy being transferred from the ore to the diamond, a spontaneous radioactive disintegration of the ore. This is a very slow process, requiring millions of years for the uranium to reach its stable (nonradioactive) phase (Ashbaugh 1988).

During this process, the highly energetic particles released by the uranium eventually cause damage (on an atomic scale) to the diamond crystal, which gradually induces a pure green colour of natural origin. The problem with these greenskinned diamond crystals, is that the colour is polished off by the cutter, resulting in a colourless gem similar to what Earl Marshall described .

So how do the exceptionally rare bottle green coloured diamonds occur? If all the green skin colour is removed during cutting, how can a natural diamond rightfully claim to have a pure bottle green body colour of natural origin? The

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answer lies in the uranium and the energetic particles it emits, specifically alpha, beta, and gamma particles. The alpha (helium nuclei) and beta (electron) particles are electrically charged, one positive the other negative, so when they strike the surface of a diamond crystal buried in the ground, they are stopped at the diamond's outer surface , penetrating only a few microns at most. This causes localized damage to the diamond structure. Such damage on an atomic scale is actually a vacancy (a site where a carbon atom or an electron used to be in the diamond lattice).

This radiation-induced defect (neutral vacancy) now absorbs a certain portion of the visible spectrum, specifically in the red end at a wavelength of 741 nm, resulting in a complimentary green colour in the form of a tiny green spot or many green spots all over the surface. The more grains of uranium ore that surround the crystal the more green radiation spots a diamond will exhibit on its surface. Over time

FIGURE 4.3. Rough alluvial diamond crystal (type la) from Guiana, showing green surface stains resulting from natural radiation.

as the radiation damage progresses and the spots enlarge, they begin to coalesce on the surface forming some of the most unusual and intricate colour patterns I have ever witnessed in nature (Figs. 4.3 and 4.4) . In order to express this unusual diamond colour phenomena to its highest potential, I asked Tino Hammid (a professional gemstone photographer) to take a photograph (Fig. 4.5) , and Nizam Peters (a diamond cutting instructor who also teaches a rough grading course at AIDC) to take a photograph (Fig. 4.6). I think you will agree that there is an intricate design to the randomly distributed, naturally occurring, radiation-induced, green "spots," "stains," "halos," or "mottled skin" as they are referred to by diamond researchers (Crowingshield 1962fa & 1967wn; Meyer 1965; Mendelssohn 1979; Shigley 1990; Vance 1972).

FIGURE 4.5. Rough alluvial diamond crystal from South Africa, showing green surface stains resulting from natural radiation.

FIGURE 4.4. Rough alluvial diamond crystal (type Ila) from Guiana, showing green surface stains resulting from natural radiation.

FIGURE 4.6. Rough alluvial diamond crystals from Central African Republic, showing green surface stains resulting from natural radiation.

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If the highly energetic alpha and beta particles do not contribute to giving natural green diamonds their beautiful body colours, then what does? The answer is in the gamma particles, which are uncharged particles similar to high energy x-rays. Gamma particles (rays) are much weaker than the alpha particles, yet they can penetrate through a diamond (much like x-rays penetrate the human body), causing radiation-induced (vacancy) defects at various points inside the body of the rough diamond crystal. Since gamma radiation is much weaker than the other particles striking the diamond, the effect of gamma radiation on colouring the interior of a diamond crystal is negligible in cases where the diamond has been in contact with the radioactive substance less than, say, 10,000 years. Thus, natural colour diamonds with an obvious green body colour are exceptionally rare, and very old, representing long periods of physical contact between uranium ore and a diamond crystal (see Christie 's NY Oct 1992 Lot 727).

What usually happens, according to scientific speculation , is that the radiation damage builds up over long geologic periods of time and forms a thick layer of damage to the outer surface. While this looks like a thick black skin upon casual inspection, it is actually a very dark green layer of alpha particle damage (Fig. 4.7).

Natural alpha-radiation damage can actually expand the lattice constant (distance between adjacent carbon atoms) causing the outer skin of the rough diamond crystal to systematically crack-off (spall) as radiation proceeds (Fig 4.8) (Vance 1972).

FIGURE 4. 7. The girdle edge of a polished green diamond, showing a dark green layer of natural radiation damage on the surface, magnified 30X.

FIGURE 4.8. A tiny area of intense natural radiation damage near the girdle edge of a polished green diamond. Note that the dark "skin " is partially brokenoff revealing numerous overlapping green and brown radiation stains, magnified 40X.

However, at the same time the alpha-induced surface colouration is accumulating, the gamma-induced body colouration is accumulating as well, albeit at a much slower pace (Collins 1978). Since the rate at which the particles are emitted by the uranium ore is constant, referred to as the half-life, there is actually a ratio between the alpha-induced damage on the surface and the gamma-induced damage inside the crystal. Accordingly, there is a visual colour ratio that exists between

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the surface colour and the body colour. Experienced rough dealers who work with these green-skinned diamonds can often estimate the interior colour by just looking at the amount of surface colour. If the skin is nearly black this would indicate a high dose of radiation, and experience would lead one to assume the colour on the inside might be a pronounced green, often referred to as "bottle" or "emerald" green (Fig. 4.9).

"... a fine emerald-green brilliant diamond... which before cutting had a sooty black appearance; another specimen of similar appearance retained its black colour almost entirely after cutting ... "

J.J. Tschudi

1862

Well, I could continue with this story of how a diamond might acquire a pure green colour naturally. But the point I am making concerns rarity, true rarity. It is important to remember that whenever someone is talking about true rarity in a coloured diamond , they are actually speaking about the manner in which a diamond acquired its colour from nature. As stated earlier, this is based on objective criteria and is different for every single colour. Thus the manners in which a yellowish green diamond acquired its colour as opposed to a bluish green or an olivish green, represent three entirely different sets of physical circumstances in the earth -

one

set of circumstances being more involved and intricate and infrequent (i .e., truly rarer) than another.

FIGURE 4.9. (Left to right) Two bottle green diamonds, a bluish green (Christie 's NY Oct 1992 Lot 72 7) and a pure green (Aurora No. 86) with a colourless diamond (far left).

This arcane world of true rarity in coloured diamonds, is a fascinating one of atoms and electrons, colour centers and absorption bands, structural defects and impurity atoms, and all sorts of other objective causes dealing with the physical world. Read what a noted diamond scientist has to say on the subject of defects in diamonds (Burls 1967).

"... The major reason for studying defects in diamond is to learn what they can tell us about the history of the diamonds. It is a truism in diamond lore that every stone is an individual: but the perfect crystal is a blank page. The individuality of every diamond resides in its imperfections, and these afford our only clue to what has happened to that crystal since its birth. The surface tells us the last things that happened to it, and the interior something about its origin, its growth, and perhaps the changes in temperature, pressure and shear stress to which it has been subjected, if we can learn to read the record aright. " FC. Frank

1967

We have now seen that true rarity is multi-dimensional, and this makes it difficult for most people to grasp because it is not easy to appreciate or understand the physical nature of how diamonds acquire their colours. I, myself, am constantly learning more about the subject every day, through personal experience

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and by reading research papers written by dedicated and inquisitive diamond researchers who pursue answers to these questions. For readers who are interested in learning more about the origins and causes of diamond and gemstone colours, and hence learn more about true (natural) rarity of colours in nature, I recommend reading anything published by Collins, Fritsch, Gubelin, Nassau, Rossman, or Shigley; these people understand this aspect of rarity better than anyone. For readers who FIGURE 4. 10. Natural pink diamonds (left to right) Aurora Nos. 198, 35, 194, 9, 172, 55, and 143.

wish to know more about false (commercial) rarity, I recommend speaking with any knowledgeable coloured diamond dealer or one of the auction houses, as these people understand this aspect of rarity better than anyone.

Obviously, I could have chosen to explain how pure pink instead of pure green diamonds acquire their colour in nature. I could have explained that all natural pink diamonds (Fig. 4.10) show evidence that they were subjected to a directional pressure in the earth when they were in a semi-solid (plastic) crystalline state.

This is referred to as plastic deformation by researchers (Lang 1967 & 1979; Orlov 1977), similar to squeezing a deck of playing cards in your hand and having each card slide past the next one by a slight amount along parallel (crystallographic) directions. In fact , the pink colour seen in all natural pink diamonds is localized along narrowly spaced parallel pink grain lines inside the body (Hofer 1985; Kane 1982) resulting from this plastic deformation (Fig. 4.11 ).

Researchers are still trying to unlock the mystery behind these structural defects and to understand how slight movements of atoms along the octahedral direction can absorb certain wavelengths of (green) light causing pink colour. Add to this various impurity atoms (e.g ., nitrogen and/ or hydrogen) along with fluctuating temperature and pressure conditions associated with different types of primary diamond

deposits

(e.g.,

eclogitic, ultramafic, lamproitic), and we have a complex picture of rarity for this one colour vaFIGURE 4. 11 . Pink grain lines seen through the pavilion of a natural pink diamond, magnified 25X.

riety. Then when we consider the association that natural pink diamonds have with brown and purple graining, the question of whether a pure pink (PK) diamond is truly rarer than a purplish pink (ppPK) or a brownish pink (br-PK) becomes a puzzle unto itself.

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However, true rarity and false rarity regarding natural coloured diamonds can be put into a meaningful relationship or scale of rarity, based on knowledge of colour origin, the actual abundance of these colours, and knowledge of the preferences for certain colours in the marketplace. Since I have experience in both these areas (technical and commercial) , I have organized natural diamond colours according to what I perceive as a scale of true and false rarity. I admit this is a bold undertaking, and it may require future revision based on opinions of diamond researchers regarding true rarity (the actual frequency/infrequency of certain colours in nature) and the opinions of diamond merchants regarding false rarity (the actual hierarchy of desirable colours in the market). Regardless of any errors or omissions, and from my vantage point as a coloured diamond consultant and technician , I have formulated a workable scale of true rarity and false rarity for natural coloured diamonds. This was accomplished by examining historical records and keeping careful notes on stones of a particular colour over an extended period of time.

In order to devise this dual scale of true rarity and false rarity, we need to settle on a system of ranking rarity from top to bottom, from infrequently occurring to the frequent in nature (true rarity), and from most desirable to the least desirable in the market (false rarity) . If we consider only two levels for this rarity scale , we are limiting the scale to infrequent vs. frequent, and desirable vs. least desirable.

Clearly an expanded scale is needed to delineate between diamonds of differing rarities. After much thought, I have settled upon a five-step rarity scale, which not only provides upper, middle, and lower levels, but intermediate levels as well. In addition, when organizing unusual specimens such as coloured diamonds into any group or scale based upon a wide assortment of criteria, it is best not to have too many steps, as this will only lead to confusion, hence five levels of rarity seems both adequate and reasonable.

For purposes of everyday use by collectors, I have assigned each of the five levels of rarity a name, specific to a particular level of rarity, to denote which type of rarity one is referring to, true rarity or false rarity. The following chart lists the rarity terms I have selected for use with natural coloured diamonds, based upon popular terms spoken in the diamond trade (see Table 4.1) .

TABLE 4.1.

True Rarity

False Rarity

(Physical Laws of Nature)

(Commercial Opinions/Desires)

1.

Exceptional

1.

Extreme

2.

Notable

2.

Definite

3.

Reasonable

3.

Moderate

4.

Modest

4.

Slight

5.

Nominal

5.

Common

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Thus, in the specialized nomenclature of the coloured diamond collector, if one wishes to denote the particular level of true rarity for a natural coloured diamond, he or she can apply the appropriate word from the left column . A typical example , would be to say that a natural diamond of pure green colour is of exceptional (natural) rarity. By the same reasoning one could denote the particular level of false rarity by applying the appropriate word from the right column . A typical example, would be to say that a natural diamond of pure green colour is of extreme (commercial) rarity.

The diamond I choose in this example (pure green) is at the top rarity level for both types of rarity, true and false. While this is the case with pure green diamonds, it is not necessarily the case with other colours. Thus, in order to organize diamond colours according to the principles outlined above, I have devised a series of five rarity charts for some of the colours known to exist in natural coloured diamonds. In order to make these charts simple to read so that anyone can look at them with only a glance to access what they are looking for, I have used abbreviations for the twelve basic colours, which are explained in detail in chapters 2 and 9.

WH

white

wh

whitish

GY BK

gray

gy

grayish

black

bk

blackish

pp

purple

pp

purplish

PK R

pink

pk

pinkish

0

orange

0

br

red

reddish orangish

BR

brown

y

yellow

y

OL

olive

ol

G B

green

g

greenish

blue

b

bluish

=

brownish yellowish

=

olivish

These twelve colour varieties exist as pure colours, or in various combinations of one, two, three, or four modifiers in natural diamonds (see chapter 9). This rarity chart only deals with diamonds having one colour modifier (of varying

strength) with which I am familiar through practical experience. For example, from the orange colour variety the following colours are listed according to their rarity:

0 y-0 Y-0 r-0 pk-0 PK-0 br-0 BR-0

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pure orange yellowish orange yellow-orange reddish orange pinkish orange pink-orange brownish orange brown -orange

The reader will notice I offer no opinion of rarity for a red-orange (R-0) diamond, simply because I do not have sufficient information on such a colour. This might lead one to assume that such a colour is both exceptionally rare in the natural sense and extremely rare in the false sense. This might be correct for a red-orange diamond, yet this is not the case with other colours that were purposely left off this list such as yellow-gray (Y-GY), olive-gray (OL-GY}, greenish orange (g-0) and others.

Compared with colourless diamonds, coloured specimens exist in quite insignificant numbers."

M. Bauer

1896

"... Out of 1, 000 carats of diamond produced in a typical mine, let us assume 150 carats are of gem quality Of these perhaps 10 carats will be 'white' (0-E-F) [colourless grades] and another 20 carats will span the range from G to I [near colourless grades].

If worldwide statistics are averaged, we might find only 113 to 112 carat of 'fancy' diamond (strong, attractive colour) in this theoretical output. In other words, fancy [coloured} diamonds are many times rarer than 'white' [colourless] diamonds. "

J.E. Arem

1982

TABLE 4.2

Exceptional

Extreme

Natural Rarity

Commercial Rarity

WH wh GY gy

BK

White

bk pp pp

Gray

pk

Black

r

PK R 0

Purple Pink Red Orange

PP, r-PP

r-PP

r-PK, R-PK, 0-PK

PK, r-PK, R-PK

R, br-R, pp-R, pk-R

R, pp-R, pk-R, PK-R

0, r-0, PK-0

0, r-0

Brown

0

BR br

y y OL ol G g

B

y

Yellow

b

white whitish gray grayish black blackish purple purplish pink pinkish red reddish orange orangish brown brownish Yellow yellowish olive olivish green greenish blue bluish

Olive Green Blue

G, bk-G

G, b-G, B-G, y-G

B, G-B

B, G-B

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TABLE 4.3

Notable

Definite

Natural Rarity

Commercial Rarity

WH

b-WH

pk-PP, PK-PP, bk-PP

pp

Pink

PK, o-PK

pp-PK, PP-PK

Red

PK-R

br-R

Orange

pk-0

pk-0 , PK-0

Brown

r-BR , R-BR

r-BR , R-BR

Wh ite Gray Black Purple

g-Y, G-Y

Yellow WH wh GY gy

BK bk

pp pp

PK pk

R r

0 0

BR br y y OL ol

G g

B b

white whitish gray grayish black blackish purple purplish pink pinkish red reddish orange orangish brown brownish Yel low yellowish olive olivish green greenish blue bluish

Ol ive b-G, B-G , y-G , Y-G

Y-G

g-B

g-B

Reasonable

Moderate

Natural Rarity

Commercial Rarity

White

b-WH, gy-WH, br-WH, y-WH

WH

Gray

b-GY, B-GY, pp-GY, pk-GY

B-GY

br-PP, BR-PP, GY- PP

pk-PP, PK-PP

pp-PK, PP-PK

o-PK, 0-PK

Orange

y-0, Y-0

y-0, Y-0

Brown

pk-BR , PK-BR, ol-BR , OL-BR , pp-BR

pk-BR, PK-BR , pp-BR

Yellow

ol-Y, OL-Y, g-Y, G-Y, o-Y, 0-Y

o-Y, 0-Y

Ol ive

OL, g-OL, G-OL

OL

Green

ol-G, OL-G

ol-G , OL-G

gy-B , GY-B , bk-B

gy-B , GY-B

Green Blue

TA BLE 4.4

Black Purple Pink Red

Blue

11 2

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4

TABLE 4.5

Modest

Slight

Natural Rarity

Commercial Rarity gy-WH, br-WH, y-WH

White Gray

y-GY, wh-GY, ol-GY, g-GY, br-GY

g-GY, pp -GY, b-GY, pk-GY

Black

br-BK, gy-BK

BK

Purple

gy-PP

br-PP, gy-PP

br-PK, BR-PK, gy-PK, GY-PK

br-PK, BR-PK, gy-PK, GY-PK

Orange

br-0, BR-0

br-0, BR-0

Brown

y- BR , Y-BR , o- BR , 0-BR, bk-BR

y-BR, Y-BR, o-BR , 0-BR

Yellow

gy-Y, GY-Y, br-Y, BR-Y

ol-Y, OL-Y

Olive

gy-OL, GY-OL, br-OL, BR-OL, y-OL, Y-OL

y-OL, Y-OL,

Green

gy-G, GY-G

gy-G, GY-G , bk-G

bk

wh-B

bk-B, wh -B

pp

Pink Red

WH wh GY gy

BK pp

Blue

PK pk

R

TABLE 4.6

r

0

Nominal Natural Rarity

Common Commercial Rarity

White Gray

GY, bk-GY

GY, bk-GY, y-GY, wh-GY, ol-GY, br-GY

Black

BK, gy-BK

br-BK, g-BK, gy-BK

0

BR br

y y OL ol G g

B b

white whitish gray grayish black blackish purple purplish pink pinkish red reddish orange orangish brown brownish Yellow yellowish olive olivish green greenish blue bluish

bk-PP, BR-PP, GY-PP

Purple Pink Red Orange Brown

BR

BR, bk-BR , ol-BR, OL-BR

Yellow

y

gy-Y, GY-Y, br-Y, BR-Y

Olive

gy-OL, GY-OL, br-OL, BR-OL

Green Blue

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11 3

5 VALUE: BUYING AND SELLING At the present time , there is absolutely no doubt in the mind of any gem and jewelry professional that coloured diamonds are the most valuable gemstone on the planet , as determined on a price per carat basis (Arem 1982; Athineos 1991 ; Christie's 1996; Farrington 1903; Holmes 1987; Sielaff 1994; Sotheby's 1996). However, many of these same individuals are surprised to discover that today's reverence for "fancy colours " has developed gradually over many centuries, as news of these fabulous stones began to spread outside the royal courts of ancient Persia and the Far East. In fact , in an cient times, all diamonds were exceedingly scarce and those available for purchase were exorbitantly priced or considered unattractive by the gem and jewel connoisseurs of that era.

"... et iis (regibus) admodum paucis cognitus. "[known only to kings and to very few of them] Pliny the Elder

77 A. D.

"... parvis atque indecorus. " [small and ugly] Isidore of Seville

636 A. D.

It is from these humble beginnings, that the history, mystery, and value of coloured diamonds has gradually developed , from antiquity through the Middle Ages to the present. For example, in the seventeenth century, coloured diamonds were recognized for their unique colours and distinctly different appearance from their colourless cousins , yet they were often valued much less than colourless diamonds of so-called pure-water.

11 5

"... The District [diamond washings in the Panna district of Madhya Pradesh] is now subject to me. All diamonds found in the river are forwarded to court. Only a few days ago, a diamond arrived which had a value of Rs. 50, 000, and I hope many more will be added to my store of jewels ... Among those diamonds received, was one which

was coloured like a sapphire, it weighed several ratis, and the lapidaries valued it at Rs.3,000, though they would have given 20,000, had it been white [colourless] and

stood the test [a method of testing for flaws consisting of fixing them on the horns of fighting rams]. .. " Ibrahim Khan

1616

"... The Diamond: It is the hardest and when Cut, the most beautiful of all Stones; in knowledge whereof there is great difficulty. .. Their waters are White [colourless}, Brown, Yellow, Blue, Green, and Reddish [pink}; whereof take notice, rating them according to their waters: In our climate the perfect white Water is most esteemed."

John Fryer

1681

"... Diamonds perfectly free from colour [colourless] are said to be of the first water, but they are found of every colour of the rainbow -

red, orange, yellow, green, and

blue, and some quite black. A coloured diamond, perfectly pure and free from flaws, may be, on account of its rarity, almost as valuable as a brilliant, of the same size, of the first water [colourless]. .. " Archibald Billing

1875

Even in the mid-twentieth century coloured diamonds were still developing their reputation as a new and different source of wealth. At that time, in the 1950s, fancy colours were being offered for sale at various public auctions, yet they were often listed in the catalogues as "Fancy Diamond Ring," with no mention of the colour (e .g., Parke-Bernet 1956 Lot 95). The lack of colour description for fancy diamonds continued sporadically for the next twenty years (e.g., "A Very Large Brilliant Diamond Cushion-Shaped and of Fancy Colour" Sotheby's New York December 1960 Lot 127; "An Important Fancy Coloured Diamond" Sotheby's New York December 1960 Lot 150; "An Attractive Step-Cut Diamond of Fancy Colour" Sotheby's New York May 1962 Lot 132; "Fancy-Color Diamond Ring" Parke-Bernet, Madison Avenue Gallery, 1968, Lots 190 & 204; "Diamond and Fancy-Color Diamond Ring" Sotheby Parke Bernet, Los Angeles, 197 4, Lot 92) . However, in the 1960s, we began to see a few coloured diamonds offered for sale along with a colour description, which usually featured a common colour name such as "A Step-Cut Diamond of Light Go/den-Yellow Colour" (Sotheby's NY APR 1961 Lot 107) or "Cushion-Shaped Canary-Coloured Diamond" (Christie's LD Oct 1962 Lot 154) or "Highly Important Step-Cut Diamond of Light Canary Colour" (Sotheby's NY Jun 1963 Lot 98) or "Natural Fancy-Color Canary Diamond" (Sotheby's LA 197 4 Lot 188) or "Pear-Shaped Fancy Sherry Color Diamond" (Sotheby's NY Sep 1977 Lot 56).

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In the current market, values are intimately associated with the colour descriptions (grades) assigned to a particular stone such as "Extraordinary Fancy Intense Yellowish Green Diamond" (Christie's NY Apr 1995 Lot 597), or "Magnificent Fancy Deep Blue Diamond Ring" (Sotheby's NY Apr 1995 Lot 57 4). These colour grades incorporate both scientific facts and market opinions, therefore the interpretation of value based upon the description of colour has spawned a great debate among diamond industry professionals, collectors, and connoisseurs. In an effort to introduce order to this chaos, leading diamond grading laboratories are continually improving their colour grading methods to communicate colour more accurately (King 1994). However, there are still questions in the mind of many collectors and dealers regarding colour and value. While many believe that colour grading accuracy may be improving, the overall precision (repeatability and reproducibility) is less than desirable simply because diamond colour grading is a subjective procedure and thus prone to human error! (See chapters 7 and 8.)

In the rarefied world of coloured diamonds , one can attempt to generalize values by listing the upper limitations that have been achieved for exceptional specimens of various colour varieties (see Table 5. 1). These data are part of the public record gathered from sales held at Christie's and Sotheby's, which have occurred at various auctions over the last fifteen years.

If we take a close look at this public record of colour grades and prices per carat for each colour, it is difficult for anyone to explain how to factor in dominant hue (variety) , secondary hues (modifiers), lightness and saturation (tone), and the effect they have on each buyer's opinion of a stone. Evaluating the hue, lightness, and saturation is a necessary process when establishing value in a fancy coloured diamond (Meyer 1991 ). In addition to the colour (grade), size (carat weight) and clarity (flawless to imperfect grades) also play a role in determining value. These two necessary elements cannot be overlooked when buying or selling. The shape outline and the cutting style may also be factors , especially the effect they have on the face-up colour and beauty. These last two factors (shape and cut) are intangibles, influenced by fashion and taste, which often fluctuates from person -to-person, placeto-place, year-to-year, and from one decade to the next (Briggs 1944; Tillander 1995).

"... in colored diamonds ... the variations of quality, color and cut are so many, and the relative value of the sizes changes so frequently to accord with the demands of the market, that an exact table of prices is impossible ... " WR. Cattelle

1903

"... The factor of color is given an importance unequalled in the evaluation of any other gem. By far most diamond gems appear colorless to the untrained eye and only a few gems display decided hues such as one expects to see in varieties of corundum, for example; these are 'fancy' diamonds, very rare and very costly. .. Nevertheless, some color-grading system is employed by every dealer in [fancy} diamonds, and

affects directly and substantially the price that is charged... " J. Sinkankas

VALUE: BUYING AND SELLING

1968

117

In general, the value of coloured diamonds (whether destined for a private collection or commercial investment) , is inevitably driven by the economies of the world (Boyajian 1988; Bronstein 1994; Cockle 1996). The economic cycles of the past fifteen years have seen coloured diamonds reach new heights in value as price records were broken . Then values plateaued as world finances tightened, and then the cycle began again and even newer heights were reached . To those who regularly follow the auction sales of coloured diamonds, this does not come as news.

In fact, steady growth with brief periods of acquiescence continue to be the norm for coloured diamond valuation, all because of scarcity. To m路ake this point clear, I have included a portion of two published auction updates, one written by a gemstone financial expert over twelve years ago (Cirlin 1983) and the other written recently by the editor of a well-known diamond industry magazine (Sielaff 1994). Both articles make it clear that record prices were paid by private collectors and diamond dealers at a time when the precious gem market was "holding steady" (Cirlin 1983) or "hanging tough" (Sielaff 1994), reinforcing the idea that this cycle repeats itself over time as world finances fluctuate .

"... Fancy coloured diamonds were the star performers at both auctions. At Christie's, a fancy pink, 4. 58 carat certificate diamond, internally flawless, stole the show at $250, 000 - about $30, 000 over the high-end anticipated sales price. At Sotheby's, a magnificent fancy green diamond of 8. 19 carats, surrounded with 14 marquiseshaped diamonds and 1 round diamond of about 2. 75 carats, sold for $360, 000 (before premium) - a whopping $160, 000 over Sotheby's anticipated high price.

Fancy coloured diamonds -

now in particular -

are garnering the highest prices in

the industry - often because of their scarcity. In just about every colour but light yellow and brown, although these often bring good prices too, they're about the most indemand stones, and with subsequently high price tags ... "

8. Cir/in

1983

"... Citing the October Christie's and Sotheby's auctions in New York, U.S. coloured diamond wholesalers assert that their market is rebounding from its recent lethargy ..

The strength shown by coloured diamonds was a standout feature at both houses ... " W Sielaff

1994

Keep in mind, coloured diamond values established at auction, specifically the standard-setters or record-breakers , are usually unique stones. Hence the sight of something unique and rare at public auction forces the major connoisseurs to stretch to new financial limits (Moyerson 1980). Such was the case at Christie's in Geneva on November 15, 1990, when the top price for blue diamonds was pushed to a new height by Lawrence Graff, a connoisseur/ dealer who paid a world record price for a unique one-of-a-kind intense blue diamond of 6.19 carats (Fig. 5.1 ). However, prices for one-of-a-kind coloured diamonds are constantly be-

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5

ing challenged (Shor 1994), as witnessed in Sotheby's New York auction on October 18, 1994, when Sam Abram , also a connoisseur/ dealer, paid an equivalent per carat price for a fancy deep blue, emerald cut diamond of 20.17 carats (Fig. 5.2) . Thus, it is safe to predict that these prices paid by knowledgeable diamond professionals (in the neighborhood of US $500,000 per carat) will soon be replaced by new records of value as world demand for exemplary colours increases. In fact during this writing, a new price per carat record was set for blue diamonds in April 1995 when a 13.49-carat fancy deep blue diamond sold for US $554,670 per carat. Later that same year, the world record paid for a blue diamond at auction changed in October, then again in November when the bidding on a 4.37 -carat oval-shaped fancy deep blue diamond reached US $569 ,000 per carat (Fig. 5.3) .

.....

l

FIGURE 5.2. 20. 7-carat blue diamond.

FIGURE 5. 1.

6. 19-carat Graff blue diamond.

FIGURE 5.3. diamond.

4.37-carat blue

Coloured diamond collectors and would-be investors should also rightly assume that some of the rarest and finest coloured diamonds have traded hands in the offices and showrooms of the world's most prominent cutters, dealers, and jewelers, sometimes for more than the published auction prices . This is something the public will never hear about. Therefore, this book, or any other document (e.g., diamond price lists) cannot provide completely accurate or relevant information pertaining to coloured diamond values.

VALUE: BUYING AND SELLING

1 19

While there are published price lists for coloured diamonds, which list stones of broadly similar colour grades, these price lists are not formulas or rigid price grids (Meyer Sep 1992). Buyers and sellers (collectors) are acutely aware that these lists are price guidelines, meant to inform and educate on matters of value and not intended to set a value standard for such rare objects of art. Each coloured diamond, like a fine work of art, will ultimately rise to its highest value through the constant ebb and flow of the marketplace, controlled for brief periods of time by those who wish to possess their beauty for their own pleasures .

"... A gem should be a real possession, capable of affording pleasure to the wearer and the spectator, and, with fair usage, retaining an intrinsic and marketable value, undiminished by lapse of time."

E. W Streeter

1877

"... Diamonds of exceptional size and of unusual colours are not common articles of commerce, and their price, while always, of course, very high, depends on the number of would-be purchasers which can be found for them."

M. Bauer

1896

"... Exceptionally fine coloured diamonds have no fixed price, and, as with fine paintings, set rules do not hold... " S.H. Ball

1937

"... Some of the costliest jewels in the world are fancy [colour] diamonds. They are regarded both as natural curiosities and as collectors' items."

E. J. Gubelin

1980

".. . A collector will gladly overpay for a colored diamond, more than for any other stone."

T Horovitz

1986

(see Kaye 1986)

Ultimately, valuing a coloured diamond is as much art as science, with a final subjective reaction often overriding all objective analysis. " C.A. Meyer

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CHAPTER

5

1992

FIGURE 5.4. A selection of fancy intense pink diamonds offered in the Pink Diamond Tender 1996. Including a 3.66-carat cushion-cut (center), the largest polished pink diamond produced to date by Argyle Diamonds.

"... In the coloured diamond market, it is a standard practice to compare values on a per carat basis. However, in the world marketplace many items of commerce are valued on a per ounce standard (e.g., precious metals or chemicals). In this global context, the 0. 95-carat purplish red diamond (see Table 5.1) -

which sold at public auction in 1987

is equivalent to nearly $145 million per ounce!"

S.C. Hofer

VALUE: BUYING AND SELLING

1987

12 1

TABLE 5.1 List of the highest prices paid (per carat) at public auction, for natural colour diamonds. Diamonds are grouped according to the twelve colour varieties: White, Gray, Black, Purple, Pink, Red, Orange, Brown, Yellow, Olive, Green, and Blue.

Colour Grade

Colour Description

Carat Weight

Shape Outline

Cutting Style

Auction House

Location of Sale'

Date of Sale

Lot Number

Per Carat Price' '

White

3.92

Round

Brilliant

c

NY

Apr1993

234

$2,933

c c c c s

NY GN GN NY NY

c s s c s

NY NY SM

White Fancy Gray Bluish Gray

5.54

Round

Brilliant

Fancy

Fancy Dark

Gray

17.79

Marquise

Brilliant

Fancy

Bluish Gray

15.47

Rectangle

Emerald

Fancy

Blue-Gray

2.28

Marquise

Brilliant

Gray

2.85

Pear

Brilliant

Fancy

Black

46.53

Circular

Briolette

Fancy

Black

67 .50

Cushion

Brilliant

Fancy

Black

5.21

Cushion

Brilliant

Fancy

Black

40.04

Pear

Brilliant

Fancy

Black

18.65

Shield

Step

Fancy

Reddish Purple

0.54

Round

Brilliant

Fancy

Purple

1.04

Bullet

Step

Fancy Dark

Oct1996

532

$ 51,355

Nov1989

584

$36,037

Nov1993

663B

$34,446

Oct 1991

309

$26,535

Oct1993

357

$ 23, 100

Oct 1996

542

$ 2,418

Dec 1990

373

$ 1,466

Feb 1991

183

$ 1,040

NY NY

Apr1994

342

$631

Apr1993

207

$ 501

c c s c s

NY GN NY NY NY

Apr 1987

366

$122,222

Nov1990

211

$94,240

Apr1990

441

$56,617

Apr1996

144

$48,975

Oct1989

193

$ 4 7,300

s s c c c

GN NY NY GN GN

Nov1995

519

$ 819,201

Apr1995

587A

$ 425,304

Apr1989

363

$402,866

Nov1993

663

$ 381,306

Nov1994

436

$377,483

c c

NY NY

Apr1987

408

$926,315

Oct1996

513

$326,800

Black

Purple

Fancy

Purple

0.68

Lozenge

Step

Very Light

Purple

4.41

Round

Antique Brilliant

Fancy

Purple

1.06

Square-Octagon

Modified Brill.

Purplish Pink

7.37

Rectangle

Emerald

Pink Fancy Intense Fancy

Purplish Pink

4.92

Rectangle

Emerald

Fancy

Purplish Pink

3.14

Square-Cushion

Brilliant

Fancy

Purplish Pink

10.83

Pear

Brilliant

Fancy

Pink

19.66

Rectangle

Emerald

Fancy

Purplish Red

0.95

Round

Brilliant

Fancy

Red

0.25

Oval

Brilliant

Red

* Note: G N=Geneva, LD=London, NY= New York , S M =Saint M o ritz. * * Note: the per carat price listed represents the hammer price p lus the buyer's premium divided by the c arat w eight, as determined by the respective auction house.

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CHAPTER

5

Colour Grade

Colour Description

Carat Weight

Shape Outline

Cutting Style

Auction House

Location of Sale路

Date of Sale

Lot Number

Orange

5.54

Cushion

Modified Brill.

s s s s s

NY GN NY GN GN

Oct 1997

657

$238,718

May 1988

8

$211,113

Apr1996

302

$50,448

May 1991

360

$ 29,232

May 1992

521A

$ 21,308

Apr1987

122

$9,259

Oct 1988

126

$6,754

Per Carat Price路路

Orange Fancy Vivid

Yellow-Orange

8.93

Pear

Brilliant

Yellowish Orange

2.23

Heart Brilliant

Brilliant

Fancy Intense

Yellow-Orange

2.22

Hexagon

Step

Fancy Intense

Yellow-Orange

1.51

Fancy

Orangish Brown

8.91

Octagon

Step

Fancy

Reddish Brown

1 .14

Round

Brilliant

Fancy

Greenish Yellow-Brown

9.84

Pear

Brilliant

c c c

Fancy

Yellowish Brown

36.65

Oval

Brilliant

s

Fancy

Brown

4.02

Cushion

Brilliant

c

NY NY NY GN NY

Fancy Vivid

Yellow

13.83

Marquise

Antique Brill.

S

NY

Fancy Intense

Yellow

18.49

Pear

Brilliant

C

LD

Fancy Intense

Yellow

18.02

Square

Emerald

C

Fancy Intense

Yellow

9.05

Pear

Brilliant

S

Fancy Intense

Yellow

7.20

Rectangle

Emerald

C

GN NY NY

Fancy

Yellowish Gray-Green

7.07

Pear

Brilliant

c

Fancy

Grayish Yellowish Green

5.21

Marquise

Brilliant

Fancy

Yellowish Gray-Green

1 .35

Round

Brilliant

Fancy

Yellowish Gray-Green

4.29

Pear

Brilliant

Fancy

Greenish Gray-Yellow

1 .50

Oval

Brilliant

c s s c

NY NY GN NY NY

Fancy

Yellowish Green

3.02

Pear

Brilliant

S

Fancy

Yellowish Green

2.15

Marquise

Brilliant

S

Fancy

Bluish Green

1.28

Round

Old European

C

Fancy

Green

2.02

Cushion

Brilliant

C

Fancy

Green

0 .79

Cushion

Antique Brill.

Fancy Intense Fancy Vivid

Rectangle-Octagon Modified Brill.

Brown

Oct 1988

131

$ 5,813

May 1992

513

$ 5, 112

Dec 1986

311

$4,925

Apr 1997

679

$238,792

Jun 1990

231

$ 203,461

Nov 1990

549

$89,000

Apr1995

615

$85,359

Apr1995

565

$84,375

Apr1988

198

$ 21,937

Apr1987

380A

$21,113

Nov 1990

598

$15,620

Jun 1990

261

$ 7,700

Apr1989

267

$4,766

Apr1988

7

$564,569

Apr1995

597

$515,186

Oct1992

727

$ 197,656

Oct 1988

400

$ 196,039

S

NY NY NY NY NY

Oct 1989

199

$83,544

c c s c c

GN NY NY GN GN

Nov 1995

256

$ 569,000

Apr1995

574

$ 554,670

Yellow

Olive

Green

Blue Fancy Deep

Blue

4.37

Oval

Brilliant

Fancy Deep

Blue

13.49

Rectangle

Emerald

Fancy Deep

Blue

6.70

Heart

Brilliant

Fancy Deep

Blue

13.78

Heart

Brilliant

Fancy Dark

Blue

6.19

Round

Brilliant

Oct1995

107

$525,746

Nov1995

261

$520,000

Nov1990

551

$500,000

VALUE: BUYING AND SELLING

123