A Rare Fancy Coloured Diamond and Diamond Necklace


The articulated necklace set throughout with vari-cut 'Chameleon' diamonds of fancy dark gray-greenish yellow, fancy deep grayish yellowish green, fancy dark gray-yellowish green, fancy deep grayish greenish yellow and fancy deep brownish greenish yellow hue, weighing 13.87 carats total, accented by brilliant-cut diamonds, remaining diamonds approximately 7.50 carats total, length 42.4cm
|Accompanied by eight GIA reports stating that the 4.02 and 0.76 carat 'Chameleon' diamonds are Fancy Dark Gray-Greenish Yellow and Fancy Deep Grayish Yellowish Green colour, SI1 and SI2 clarity respectively; and the 2.18, 1.91, 1.26, 1.05, 1.01 and 0.98 carat 'Chameleon' diamonds are Fancy Dark Gray-Yellowish Green, Fancy Dark Gray-Greenish Yellow, Fancy Dark Grayish Yellowish Green, Fancy Dark Gray-Greenish Yellow, Fancy Deep Grayish Greenish Yellow and Fancy Deep Brownish Greenish Yellow colour. Reports dated 24 July 2012 to 17 November 2015.Also accompanied by an IGI report stating that the 0.70 carat diamond is Fancy Dark Grey Yellowish Green colour and VS1 clarity. Report number GT11799804, dated 7 August 2010.Also accompanied by a GIA Portrait Report entitled "The Chameleon Diamond Necklace" detailing this extraordinary phenomenon.天然彩色'變色龍'鑽石配鑽石項鏈 9枚彩色鑽石包括暗彩灰綠黃色,深彩灰黃綠色,暗彩灰黃綠色,暗彩灰綠黃色,深彩灰綠黃色及深彩棕綠黃色,共重13.87克拉,其餘鑽石共重約7.50克拉,項鏈長度42.4厘米,附8份GIA證書,GIA肖像證書及IGI證書Chameleon DiamondsFirst documented in New York in 1943 when diamond cutter Peter Kaplan noted that a diamond had changed colour while on a very hot polishing wheel, legend has it that the subsequent lady owner tried to return the stone after removing it from her safe and noting too that her previously yellow-green diamond had become a dark green in colour. In the spring of 2005, the GIA (Gemological Institute of America) published the first extensive report on chameleon diamonds, having studied a sample of 39 of the gems in sizes ranging from 0.29 to 1.93 ct. As noted in the article, the most common colour change observed in chameleon diamonds is from "olive" green to brownish yellow or yellow."Some of them exhibit changes in color when heated, while others do so after prolonged storage in the dark – these phenomena are referred to as thermochromism and photochromism, respectively.Once a chameleon diamond cools off, or is exposed to standard lighting conditions, it returns to its original "stable" color.Among the rare collections of colored diamonds encountered throughout history, "chameleon" diamonds may be the most mysterious."Distinguished Professor Ren Lu, PhD, Gemmological Institute of the China University of Geosciences, Wuhan, China:"Chameleon diamonds are the most fascinating, certainly the rarest among all natural color diamonds, and they are so mysterious because their origin of color (how the arrangement of carbon atoms are altered, i.e. color center) is still not fully understood by modern science. There is no synthetic counterpart."變色龍鑽石首次記錄於1943年紐約，鑽石切割師彼得卡普蘭注意到鑽石在拋光過程中, 因輪上的熱力而變色,傳說鑽石的女主人也曾經在打開保險箱取出鑽石後,發現她以前的黃綠色鑽石變成了深綠色而想將其退回。2005年春天，GIA（美國寶石學院）發布了第一份關於變色龍鑽石的廣泛報告，研究了39個鑽石樣本，從0.29到1.93克拉。正如文章所述，在變色龍鑽石中觀察到的最常見顏色變化是從"橄欖色"綠色到棕黃色或黃色。正如GIA所說："顧名思義, 變色龍鑽石是一些不尋常的鑽石，其顏色可以通過週邊環境條件的變化而暫時改變。它們中一些在加熱時表現出顏色變化，而其他一些則在黑暗中長期儲存後發生變化 - 這些現象分別被稱為熱致變色和光致變色。一旦變色龍鑽石冷卻，或暴露在標準光照條件下，它就會恢復原來的"穩定"顏色。在過往歷史上珍罕彩色鑽石的收藏品中，'變色龍' 鑽石可能是最神秘的。"中國地質大學(武漢)寶石學院著名教授任魯博士："變色龍鑽石最迷人，可以說是所有天然彩色鑽石中最稀有的鑽石，它們是如此神秘，因為它們的顏色來源（碳原子的排列如何被改變，即顏色中心）仍然沒有被現代科學完全理解。而且相對沒有人造的仿製品。"