Beau Sancy

The Beau Sancy is a 34.98-carat (6.996 g) modified "pear double rose cut" diamond found in India that has been owned by a number of European royal houses. In May 2012, it was sold at Sotheby's auction in Geneva for $9.57 million. The original estimated price of $2 million was lifted five times during the eight-minute battle between five buyers, before the diamond was sold to one of them who remained anonymous.

The Beau Sancy diamond takes its name from Nicolas de Harlay, Lord of Sancy, who brought the diamond to France from India where he had been the French ambassador. Its larger sibling diamond, the Grand Sancy, was sold to James I of England for his Queen, Henrietta Maria. The Beau Sancy was acquired by the Queen of France, Marie de Medicis.

From Marie de Medicis, it passed to the Dutch King William, later William III of England, and his wife Queen Mary II. In 1701 it passed from the Dutch royal family to Frederick I of Prussia.

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