GRADING THE HOPE DIAMOND By Robert Crowningshield
For the first time ever, the famous Hope diamond has need to be confirmed for the GTL report. For been graded by a widely recognized system, Al- example) in 1960 GIA's Bert Krashes had tested the though the 45.52-ct weight was confirmed, the GIA stone with a conductometer and determined that it Gem Trade Laboratory groders found the clarity-re- was semiconductive~as is characteristic of natu- cently reported as "apparently flawlessJ'-to be VS,. ral-color type IIb diamonds) which are usually Color graded "funcy darlz grayish blue,'' the Hope blue. He also remarlzed on the red phosphorescence phosphoresces an exclting red to short-wave U.l? rudiation. to short-wave ultraviolet radiation. In 1975) Her- bert Tillander suggested [in a paper presented at the 15th International Gemmological Conference) that since the stone had last been weighed before Much has been written about the history of the the metric carat had been accepted worldwidel its Hope diamond and especially the misfortunes that weight was undoubtedly greater than had here- have supposedly befallen many who have owned it tofore been reported. He subsequently persuaded (see)e,gl Patch) 1976; Balfour) 1987; Krashes) 1988). then-curator Paul Desautels to have the stone In the more than 30 years since Harry Winston unmounted and weighed: It was indeed found to be donated it to the Smithsonian Institution in 1958) 45.52 ct rather than the previously published however! the Hope has been an object of great weight of 44.50 ct. admiratian. One of the most popular exhibits at The myster$ of the Hope is further com- the Smi~hsonian~it is probably seen by more pounded by Dr. Frederick Poughls recent report people each year than any other diamond, (Westman) 1988) that the Hope was recut slightly Althpugh the Hope has been in the United while in the possession of Harry Winston in the States for most of the 20th century (since its purchase in 1911 by Evalyn Walsh McLean), it had Figure 1. Since the Hope has been removed never been formally graded. In December 1988) the from its mozznting so seldom in modern times, opportunity presented itself when GIA learned this is one of the few photographs ever tal
ABOUT THE AUTHORS ML Crowningshield is vice-president of the GIA Gem Rade Laboratory, lnc., Santa Monica and New York. Acknowledgmenis: Dave Hargeit, John King, Ingrid Nolte, Ed- die Schwartz, Tom Yonelunas, and Phil Yurkiewicz, all of the GIA GEM Rade Laboratory, participated in the grading of the Hope. John Sampson Wh~teand Russell Feather, of the Smithsonian Institution, were invaluable in making the arrange- ments for the grading session. Gems & Gemology, Vol. 25, No. 2, pp. 91-94 0 1989 Gemological Institute of America
Notes and New Techniques GEMS & GEMOLOGY Summer 1989 ..Ot '.. ~EAGEMTRADE LABORATORY, INC. Figure 2. This G1A NOW YoA. Now Yo* 10036 Sanm Monica. Cafwrta 90404 Gem Trade Labora- tory report represents the first time the DIAMOND GRADING REPORT y2rnlo-i 1.2,' 12/88 Hope has been for- mally graded by a widely recognized ThE FOLLOWING WFRE. AT THE TIME OF THF FXAMINATION THE REOSYMBOLS DENOTE INTERNALCHARACTERISTICS. GREEN CHARACTERISTICSOF THE DIAMOhO DESCRIBED HEREIN BASE0 SYMBOLS DENOTE EXTERNAL CHARACTERISTICS.SYMBOLS system. UPON 10%HiNOCULAR MAGNIFICATION DlAMOhDLlTL AN0 MASTER INDICATE NATURE AND POSITION OF CHARACTERISTICS.NOT COLOR DIAMONDS ULTRA VIOLET. MILLIMETER GAUGE. DIAMOND NECESSARILY THEIR SIZE MINOft DETAILS OF FINISH NOT BALANCE PROPORTIONSCOPE SHOWN. KEY TO SYMBOLS - FEATHER
f BRUISE SHAPE AND CUT l?USHInN AN I'IOLIE: BRIL.LIANT . CHCP Moasuremms 25.60 X 21.78 X 12 00 MM. EXTRA FACETI' SHiIWN IN BLACK weight 45.52 CARATS
PROPORTIONS Dep!h 55.1% Table 53% Girdle VERY THIN TO SLIGHTLY TH1C:K + FACE'l'E.'U cu!et VKRY LARGE: FINISH ~o~ish ROOD Syminolry FAIR TO GOOD
CLARITY GRADE US1
COLOR GRADE FANCY COL-OR 9 SEE COMMENTS ~bowenco NONE
COMMENTS:
FANCY WiRK ORAY ISH-BLUE , NATURAL COLOR.
WHITISH GRAINING IS PRESENT.
zm'i GEM TRADE LABORATORY, INC.
Copyright 0 1968 GIA Gum Trade Laboiakxy. Inc. NOtoOIMJkMVltaMW
1950s. It is puzzling that the actual weight was not SHAPE AND CUT reported to the Smithsonian at the time of dona- In the presence of the graders, Smithsonian gem tion (J. White, pers. comm., 1989). collection curator John Sampson White weighed For the present study, the GTL staff members the 25.60 x 21.78 x 12.00 mm cushion antique provided a Mark V Gemolite microscope, Polaroid brilliant on an analytical balance. The 45.52-ct plates, a long- and short-wave fluorescence unit, a weight reported in 1975 was confirmed. conductometer, a camera for photography of the inclusions, and two ColorMasters with a fluores- PROPORTIONS cent daylight equivalent source. The results of We calculated depth percentage to be 55.1% and their efforts are shown in figure 2 and reported the table 53%.The girdle, which is faceted, ranges below. from very thin to slightly thick. Although the
92 Notes and New Techniques GEMS & GEMOLOGY Summer 1989 Figure 3. Although historically the Hope was Figure 4. Also affecting the clarity of the Hope believed to be "of the greatest purity.'' close ex- is the graining shown here at 10 x magnifica- amination with 10 x magnification revealed tion. Because of the graining, the clarity could some wear marks, such as the abraded table never be better than VVSi, Photomicrograph by edge shown here, in addition to a few small David Hargett. feathers and bruises. Photomicrograph by David Hargett. and notations are: Blue 7.511.5 (D 02/25/53). It should be noted here that most blue diamonds have culet is very large, symmetry was found to be fair a perceptible amount of gray. to good. The polish is good. Although there was no fluorescence to long- wave ultraviolet radiation, and its presumed red CLARITY GRADE fluorescence to short-wave U.V appeared to be The clariti'of the Hope has been variously noted as masked by the visible light from the ultraviolet "all perfection without specks or flaws" (Fran- unit, we were fascinated to see the strong red qillon, 1812))"of the greatest purity" (Hertz, 1839), phosphorescence to short-wave U.V (figure 5)) "a perfect brilliant" (Bauer 1904))and "apparently flawless" (1975 Smithsonian data, as reported in Patch, 1976). The GTL clarity grade of VSl was Figure 5. One of the most distinctive charac- based on the few wear marks that the stone has teristics of the Hope diamond is its distinct red phosphorescence to short-wave ultraviolet radia- accumulated during its adventures over the years tion. Photo 0 John Nels Hatleberg. (figure 31, a few minor feathers, and whitish grain- ing (figure4). Although whitish graining is charac- teristic of natural-color blue diamonds, it is not always present to the extent that it will affect the clarity grade, as it does on the Hope. Because of the graining, the highest grade possible for this stone would be a VVS,.
COLOR GRADE Like the clarity, the color of the Hope has also been described in a number of different ways since the stone in its present form first appeared in the literature in 1812. According to Franqillon (18121, r the Hope is a "superfine deep blue"; in the Hope catalog (Hertz, 1839),it is described as a "fine deep sapphire blue." The 1975 Smithsonian description (as reported in Patch, 1976) is "dark blue, often ~ described as steel blue." Our graders determined the color to be a "fancy dark grayish blue." The ColorMaster description
Notes and New Techniques GEMS & GEMOLOGY Summer 1989 93 which lasted 15-20 seconds. Such red phosphores- most famous blue diamond -unusual for its large cence is not unknown in blue diamonds, but it is size, depth of color, and the rich, if often tragic, limited almost exclusively to dark blue stones and history that has been attributed to it. The grading is seldom as intense as that seen in the Hope. of the Hope by the GIA Gem Trade Laboratory is part of an ongoing program to more thoroughly CONCLUSION document such notable stones (see, e.g, Fryer and The Hope diamond is undoubtedly one of the most Koivula, 1986) for the benefit of future gemolo- famous stones in the world. Certainly it is the gists.
REFERENCES Balfour 1. (1987) Famous Diamonds. Collin, London. Precious Stones Formed by Henry Philip Hope, Esq. Bauer M.[ 19041 Precious Stones. Reprinted by Charles E. TUttle William Clowes and Sons, London. Co., '~utland,VT Krashes L. (1988)Harry Winston: The UltimateJeweler, 3rd ed. Francillon 1. (18121 Statement and sketch regarding a 177-erain Harry Winston, Inc., New York, and the Gemological deep blue diamond. Reproduced in -s. S. Patch, -Blue Institute of America, Santa Monica, CA. Mystery: The Story of the Hope Diamond, Smithsonian Patch S.S. (1976)Blue Mystery: The Story of the Hope Diamond. Institution Press, Washington, DC, 1976. Smithsonian Institution Press, Washington, DC. Fryer C.W., Koivula J.I. (1986)Anexamination of four important Westman B.J. (19881 The enigmatic Hope. Lapidary Journal, gems. Gems a) Gemology, Vol. 22, No. 2, pp. 99-102. Vol. 41, No. 12, pp. 4245, 105. Hertz B, (1839) Catalogue of the Collection of Pearls and
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94 Notes and New Techniques GEMS & GEMOLOGY Summer 1989