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An Important Exhibition of Seven Rare Gem Diamonds

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An Important Exhibition of Seven Rare Gem Diamonds NOTES &NEW TECHNIQUES AN IMPORTANT EXHIBITION OF SEVEN RARE GEM DIAMONDS John M. King and James E. Shigley this was the historic 41 ct Dresden green diamond, which was exhibited on a rare loan from the Green From late June to mid-September 2003, seven Vaults in Dresden, Germany, in October 2000 important gem diamonds went on temporary pub- (“Harry Winston . .,” 2000). The exhibition of lic display at the Smithsonian Institution in these seven diamonds in the same setting attests to Washington, DC, in an exhibit titled “The the rarity of this special collection. “The Splendor Splendor of Diamonds.” These diamonds, one of Diamonds” at the NMNH includes the 203.04 ct colorless and six colored, are some of the rarest in colorless De Beers Millennium Star as well as six the world: the 203.04 ct D-color De Beers exceptional diamonds that represent some of the Millennium Star, the 101.29 ct Fancy Vivid yel- rarest of naturally occurring colors. On the initia- low Allnatt, the 59.60 ct Fancy Vivid pink Steinmetz Pink, the 27.64 ct Fancy Vivid blue tive of GIA representatives and with the sponsor- Heart of Eternity, the 5.54 ct Fancy Vivid orange ship of the Steinmetz Group, the seven diamonds Pumpkin, the 5.51 ct Fancy Deep blue-green were brought together from private collections Ocean Dream, and the 5.11 ct Fancy red throughout the world. Each is unique in its combi- Moussaieff Red. This article provides background nation of size, color, and quality. information on these spectacular diamonds and a Over the years, GIA staff members have exam- record of some of the gemological observations ined many important gemstones as part of our labo- obtained during their quality grading by GIA. ratory grading services and for research purposes. These opportunities have allowed us to characterize and document the gemological properties of a num- rom June 27 through September 15, 2003, “The ber of unique diamonds in public and private collec- Splendor of Diamonds,” a collection of unique tions that would otherwise not be available for gem diamonds, is on temporary display at the gemological study. Fryer and Koivula (1986, p. 102), FNational Museum of Natural History (NMNH) at in their account of the examination of four impor- the Smithsonian Institution in Washington, DC (see tant gemstones on public display for a limited time figure 1). This museum is the home of the U.S. (the Star of Bombay sapphire, the Portuguese dia- national gemstone collection, and is where the mond, and the Marie Antoinette diamond earrings), famous 45.52 ct blue Hope diamond has resided concluded with this statement: “We hope that our since its donation by Harry Winston in 1958. Since examinations will provide a more complete record its renovation in 1997, the Harry Winston Gallery in the Janet Annenberg Hooker Hall of Geology, Gems, and Minerals has been one of the most popu- See end of article for About the Authors and Acknowledgments. lar sites in the museum. Typically around two to Authors’ note: This article contains a number of photos illustrating sub- three million people visit this hall every summer (J. tle distinctions in color. Because of the inherent difficulties of control- E. Post, pers. comm., 2003). ling color in printing (as well as the instability of inks over time), the color in an illustration may differ from the actual color of the diamond. On only one other occasion has another impor- GEMS &GEMOLOGY, Vol. 39, No. 2, pp. 136–143. tant diamond been displayed in the same room; © 2003 Gemological Institute of America 136 NOTES AND NEW TECHNIQUES GEMS &GEMOLOGY SUMMER 2003 Figure 1. This collection of extraordinary gem diamonds is on temporary display at the National Museum of Natural History at the Smithsonian Institution in Washington, DC, during Summer 2003. Counter-clockwise from center, the 203.04 ct De Beers Millennium Star (courtesy of De Beers LV), the 59.60 ct Fancy Vivid pink Steinmetz Pink (courtesy of Steinmetz Group), the 27.64 ct Fancy Vivid blue Heart of Eternity (courtesy of a private collector), the 5.54 ct Fancy Vivid orange Pumpkin (courtesy of Harry Winston Inc.), the 5.11 ct Fancy red Moussaieff Red (courtesy of House of Moussaieff), the 5.51 ct Fancy Deep blue-green Ocean Dream (courtesy of Cora Diamond Corp.), and the 101.29 ct Fancy Vivid yellow Allnatt (courtesy of SIBA Corp.). Photo by Chip Clark, courtesy of the Smithsonian Institution. on these stones for future researchers, and that the continuation of this kind of documentation for opportunity will become available to provide simi- gemologists and the public. lar reports on other named pieces as we seek to GIA has issued Diamond Grading or Colored learn more about these touchstones of gemology.” Diamond Grading Reports on all seven of these dia- Since then, Gems & Gemology has published monds. Understanding the importance of the dia- gemological reports on the Hope Diamond monds requires an understanding of their grading, (Crowningshield, 1989), the Dresden Green (Kane et inasmuch as all are extraordinary for their size in al., 1990), and, most recently, the 128 ct Star of the their color grades. Colorless to light yellow dia- South (Smith and Bosshart, 2002). The information monds are color graded against a set of “master color on the seven diamonds discussed here represents a comparison diamonds,” and their color grade is NOTES AND NEW TECHNIQUES GEMS &GEMOLOGY SUMMER 2003 137 expressed as a set of letters from “D” to “Z” accord- ing to the grading system established by GIA in the early 1950s. For diamonds in the standard colorless to light yellow or brown range, those that are “most colorless” (“D” in the GIA system), like the De Beers Millennium Star, are not common and are typ- ically valued much higher than the next grade. For colored diamonds, the color grade is by far the most important factor in their value. They are graded using a series of “Fancy” grade terms that refer to a three-dimensional color space. Those dia- monds in the “end grades” of Fancy Intense, Fancy Deep, and Fancy Vivid are the most strongly colored and valued. For more information, please see the articles by King et al. (1994, 1998, 2002) which elab- orate on GIA’s fancy-color diamond grading system. The following takes a brief look at the known history of each of these special diamonds and sum- marizes the gemological observations made during grading by GIA. THE DE BEERS MILLENNIUM STAR In the early 1990s, an unnamed miner in an alluvial digging in the Mbuji-Mayi district of Zaire (now the Figure 2. Shown here is the 777 ct piece of rough from Democratic Republic of Congo) discovered a 777 ct which the 203.04 ct De Beers Millennium Star was piece of rough (figure 2), the sixth largest “colorless” cut. Courtesy of Steinmetz Group. gem-quality diamond ever found (Balfour, 2000). De Beers purchased the large crystal fragment on the open market. Following three years earlier (Balfour, 2000). The centerpiece of of study, planning, and work by the this collection was the De Beers Steinmetz Group on three conti- Millennium Star; all would soon be nents, the original crystal was the focus of one the most flam- divided into three parts. The boyant robbery attempts in largest diamond cut from modern history (see below). this crystal was a 203.04 When graded by GIA in ct, 54-facet pear-shaped 1997, the De Beers Millen- brilliant measuring 50.06 nium Star was noted to be 36.56 18.54 mm. De “D” color and Flawless (no × × Beers called it the De internal or surface clarity Beers Millennium Star. characteristics were seen In late 1999, the “De using a binocular micro- Beers Millennium scope and a fully corrected Jewels” exhibit was 10 loupe). It exhibits × unveiled at the Millen- excellent polish and sym- nium Dome in London. metry, and it has no fluores- This unique collection of cent reaction when exposed diamonds was assembled to to long-wave ultraviolet (UV) mark the passing of the mil- radiation. Large, colorless rough lennium, an event De Beers crystals with few or no mineral had anticipated since purchasing inclusions are usually type IIa dia- the enormous piece of rough years monds (see Fritsch and Scarratt, 1992, 138 NOTES AND NEW TECHNIQUES GEMS &GEMOLOGY SUMMER 2003 for more information on diamond types); the labo- due to aggregated nitrogen in triples (clusters of ratory confirmed that the De Beers Millennium three atoms, called the N3 center), which is known Star is a type IIa. in traditional gemological terminology as the “cape” absorption series (GIA Diamond Dictionary, 1993). Among colored diamonds, yellow and brown THE ALLNATT are the most common colors, but natural-color dia- This strongly colored yellow diamond is thought monds of this size with this strength of yellow are to have originated from the De Beers mine in extremely rare. This is one of the largest strongly South Africa, which produced a number of large colored yellow diamonds ever seen in the yellow diamond crystals during its early years of GIA Gem Laboratory. production (Balfour, 2000). It is named for its former owner, Major Alfred Ernest Allnatt, a British soldier, sportsman, art patron, and noted THE STEINMETZ PINK philanthropist who purchased the diamond in Both intriguing and highly val- the early 1950s. ued, pink diamonds have been Originally the Allnatt weighed 102.07 ct and treasured for many hundreds of was graded Fancy Intense yellow when it was pur- years. Adding to this allure are chased at the Christie’s Geneva May 1996 auction the few famous pink diamonds (for a total price of US$3,043,496).
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