An Alexandrite of Russian origin sets world auction record for an Alexandrite at Christie's Geneva May 14,2014 Magnificent Jewels sale

  • Thanks Mike for your update, and Joan for your sharp observation and gemlite for your subsequent confirmation. It's indeed puzzling how the central 5.40-carat, catseye alexandrite in the first image appears purple the usual color under incandescent light, while the smaller stones in the alexandrite surround appears green, the usual color when exposed to daylight.


    One possible explanation for this apparent contradiction, is selective illumination. While the central catseye alexandrite has been selectively exposed to incandescent illumination using a point source, which can be controlled and directed to a desired area, causing the purple color, the stones of the alexandrite surround had been left out of this selective illumination, still exposed to normal daylight and hence remaining green.


    The other explanation, which is highly unlikely, is that the alexandrite surround is actually made up of a different kind of green colored stone, which is not alexandrite, and hence do not become purple on exposure to incandescent light.

  • An image of an exceptional Sri Lanka alexandrite in incandescent light, taken by International Colored stone Association photographer Bart Curren, appears in several websites. The perfect cabochon-cut of this alexandrite, combined with the brownish-purple color in incandescent light and the very sharp and distinct chatoyancy is indeed a very rare spectacle. I am uploading an image of this extremely rare catseye alexandrite for the benefit of our members.

  • The image under daylight of ICA's Sri Lanka catseye alexandrite in incandescent light, is unfortunately not available for comparison. However, two images of a 15-carat, stunning catseye alexandrite, one in daylight and the other in incandescent light, appearing in a web article titled "Russian Alexandrite by Peter Bancroft" in Pala International's website, http://www.palagems.com/alexandrite_russia.htm would hopefully compensate for this shortcoming.


    Another stunning catseye alexandrite from the website gem2000.com with the URL http://gem2000.com/news/2011/0…buy-in-fine-alexandrites/ also has a distinct color change from dark green in daylight to dark purple in incandescent light and a prominent chatoyancy with a sharp catseye effect.

  • A stunning 10.02-carat, oval cabochon-cut, Ceylon catseye alexandrite with a strong catseye effect and prominent color change from brownish-green in daylight to brownish-purple in incandescent light appeared at Christie's Hong Kong, Jewels : The Hong Kong Sale, held on November 29, 2010. The alexandrite was set as the centerpiece of an 18k yellow-gold ring, flanked by old mine-cut diamonds. The lot was accompanied by two lab reports by SSEF and GRS certifying the alexandrite as a natural chrysoberyl of Ceylon origin, with no indications of any treatment, with strong catseye effect and a moderate color change. A moderate pre-sale estimate of US$16,000 to 26,000 was placed on the ring, which sold above the upper estimate for US$38,820 working out to a ppc-value of US$3874.


    Another stunning catseye alexandrite and diamond ring appeared almost one year later at Sotheby's Hong Kong Magnificent Jewels and Jadeite sale held on October 5, 2011. The round cabochon-cut catseye alexandrite weighing 13.14 carats was mounted as the centerpiece of a 18k white gold ring, framed by a diamond surround consisting of pear-shaped and brilliant-cut diamonds totaling 3.40 carats in weight. The lot was accompanied by a Gubelin report, that certified the natural origin of the stone, its distinct color-change from brownish-green in daylight to purplish-red in incandescent light, and a well-centered and pronounced chatoyancy. The GGL report however did not commit itself on the country-of-origin of the stone, probably because the characteristics of the stone, and the nature of inclusions did not match with that of known sources such as Russia, Sri Lanka, Brazil etc. Despite the uncertainity of the country-of-origin of the stone the alexandrite performed quite well at the auctions selling above the presale estimate of the lot at US$ 57,817 - 68,095 for US$71,949 (PPC- US$5,475)

  • Thanks John for your update. It seems that the 13.14-carat, round cabochon-cut catsye alexandrite has fared better, fetching a ppc-value of US$5,475 than the 10.02-carat oval cabochon-cut Ceylon alexandrite, which sold for a ppc-value of only US$3,874, despite the fact the former stone was not supported by a country-of-origin report. What are possible causes for this discrepancy?

  • Thanks John for your update and Mike for the question arising from John's update. It is indeed true that the 13.14-carat catseye alexandrite of unknown country-of-origin had performed much better than the 10.02-carat, Ceylon catseye alexandrite.
    One possible reason for this is the pronounced and dramatic color change effect of the 13.14-carat catseye alexandrite from a dull brownish-green in daylight to a vibrant purplish-red under incandescent light. Even though in the case of the 10.02-carat, Ceylon catseye alexandrite only the image of the stone under incandescent light is available, that image alone is sufficient to show that the color change in this stone will not be dramatic as the other gemstone. The Ceylon catseye alexandrite has a brownish-purple color under incandescent light, but the color is not evenly distributed, which also might have contributed to the lower ppc-value of the stone. Under daylight it turns to a brownish-green color, also not evenly distributed.
    Inspite of the uneven color distribution in the Ceylon sapphire the chatoyancy is very prominent in this stone, with a centrally placed very distinct catseye. Hence, the chatoyancy of the stone did not have a depressing effect on the price of the stone.

  • An alexandrite and yellow diamond ring bearing Lot No. 1573, appeared at Sotheby's Hong Kong Magnificent Jewels sale, held on April 8, 2013. The centerpiece of this platinum and yellow-gold ring was a 2.85-carat, circular-cut Brazilian alexandrite, surrounded by eight oval-shaped yellow diamonds, resembling petals of a flower, and eight circular-cut smaller alexandrites mounted at a lower level, alternating with the petals and resembling green sepals of a flower. Total weight of yellow diamonds was 3.95 carats and total weight of circular-cut alexandrites was 3.10 carats. A GGL report accompanying the lot, certified that the 2.85-carat alexandrite is a natural stone of Brazilian origin, with a pronounced color change from green in daylight to purple in incandescent light. A presale estimate of US$42,511 - 48,952 was placed on the lot which sold above the upper estimate for US$51,528, working out to a ppc value of US$8,660 for the alexandrites.

  • Thanks Sunil for your update. The floral design of this alexandrite and yellow diamond ring is fantastic and the very pronounced color change from green in daylight to purple in incandescent light is characteristic of the highest quality Brazilian alexandrites.

  • Two catseye alexandrite lots and a third normal alexandrite lot appeared at Christie's Jewels : The Hong Kong Sale held on May 26, 2009. The catseye alexandrite lots are Lot 1523 and Lot 1525. The normal alexandrite lot is Lot 1524.

    Lot 1523 is a Catseye Alexandrite and Diamond Ring. The ring of floral design is set with a 6.32-carat, oval-shaped, Brazilian catseye alexandrite as centerpiece, within a rose-cut alexandrite surround, and a brilliant-cut diamond trim, mounted in platinum. A GGL report accompanying the lot certified the Brazilian origin of the alexandrite, with a pronounced color change from green in daylight to reddish-purple in incandescent light and a distinct and well-centered chatoyancy. A pre-sale estimate of US$36,292 - $49,253 was placed on the lot, which sold above the upper estimate for US$61,568. The ppc value of the stone works out to US$9,742.


    Lot 1525 is an interesting Catseye Alexandrite and Diamond Necklace, designed as a line of graduated oval-shaped catseye alexandrites, consisting of 20 large oval-shaped catseye alexandrites, alternating with 20 small round catseye alexandrites, spaced by three round brilliant-cut diamonds between a large and small alexandrite. The gemstones are mounted in platinum and the length of the necklace is 42.0 cm. The total weight of the 40 catseye alexandrites is 22.69 carats. The image of the catseye alexandrite necklace is apparently taken in daylight, and hence all the alexandrites appear dark green. Interestingly, every alexandrite in the necklace shows a very prominent chatoyancy. Unfortunately, the neckalce was not accompanied by a lab report from a recognized gemological laboratory, certifying the natural status of the alexandrites and specifying the country-of-origin of the stones. This explains the relatively low price of US$40,505 realized by the necklace, within the pre-sale estimate of US$32,403 - $45,365. The ppc-value of the alexandrites also work out to a ridiculously low price of US$1,785.

  • The catseye alexandrite and diamond necklace higlighted by Maryjewel is indeed a very rare piece of jewelry. But, what puzzles me most was how it was possible to assemble together 20 large oval-shaped, graduated catseye alexandrites alternating with 20 small round catseye alexandrites to produce the necklace, when finding just one alexandrite in nature is an extreme rarity. Catseye alexandrites are even rarer than normal alexandrites in nature. Hence, the task of putting together such a necklace becomes more complicated. In the absence of a lab report, one might be led to the conclusion that the catseye alexandrites in the necklace are actually lab-grown or synthetic. Unless, the catseye alexandrite rough stones that were subsequently converted to cabochons, were collected over a period of time, from a prolific source of alexandrites such as the Hematita mine in Brazil or the graduated catseye alexandrites were cut from a larger catseye alexandrite rough crystal, the satellite stones still maintaining the chatoyancy.
    This explains the ridiculously low ppc value of US$1,785 for these alexandrites.

  • Thanks Joan for your critical analysis of the Catseye Alexandrite Necklace highlighted by Maryjewel. Your observations are perfectly in order. The catseye alexandrites in the necklace appear to be genuine alexandrites with their characteristic dark green color in daylight and prominent chatoyancy. However, the uniformity in shape, color, and chatoyancy of all the stones in the necklace, is too good to be genuine, unless it was supported by a lab report from a renowned gem-testing laboratory. Further more the registering of a low ppc-value of US$1,785 only for the alexandrites, seem to consolidate the suspicions that the stones are not genuine natural alexandrites, though the absence of a lab report might have contributed to it.

  • The normal alexandrite lot 1524, that appeared at Christie's Jewels : The Hong Kong Sale, held on May 26, 2009 was an Alexandrite and DIamond Platinum Ring, designed as a flower, centering upon a heart-shaped alexandrite weighing 2.16 carats. The four petals of the flower are pave-set with smaller alexandrites and the hoop of the ring mounted with diamonds. A lab report by GGL certified the natural Brazilian origin of the 2.16-carat alexandrite with its pronounced color change from bluish-green in daylight to purple in incandescent light. The lot sold for a moderate price of US$27,543 within the presale estimate of US$19,442-$32,403. The ppc value of the stone works out to US$12,751.