On Tuesday May 12, Sotheby’s realized $9,488,754 (CHF 10,498,500 / €7,024,336) for a fancy vivid blue, internally flawless cushion-shaped diamond weighing 7.03 carats. This is the highest price for a fancy vivid blue diamond sold at auction and the world-record price per carat for any gemstone sold at auction – $1,349,752. The sale was held in Geneva, and the price topped the pre-sale estimate of $5.8-8.5 million.
The diamond, which was cut from a 26.58 carat rough, was discovered in 2008 at Petra Diamonds’ historic Cullinan diamond mine in South Africa, the world’s most consistently reliable source of blue diamonds. The Gemological Institute of America (GIA) graded the stone as fancy vivid blue in color and internally flawless in clarity, the highest possible grading for a blue diamond. The winning bidder, who wishes to remain anonymous, has not yet exercised his or her privilege to name the stone.