Important and perfectly matched pair of unmounted brilliant-cut diamonds. photo courtesy Sotheby's

Two unmounted brilliant-cut diamonds each weighing 10.88 carats. Estimate 25,000,000—30,000,000 HKD. Lot Sold 37,620,000 HKD

Accompanied by GIA reports numbered 2115479019 and 2116039611, dated 8 December 2009 and 27 July 2010, stating that the 10.88 carat diamonds are D colour, Flawless clarity, with Excellent Cut, Polish and Symmetry; also accompanied by diamond type classification reports stating that both diamonds are determined to be Type IIa diamonds. Type IIa diamonds are the most chemically pure type of diamond and often have exceptional optical transparency.

Sotheby's. Magnificent Jewels & Jadeite. 06 Oct 10. Hong Kong www.sothebys.com