Rare Blue Diamond sells for $9.6 million

A rare blue diamond ring was auctioned by Bonhams April 24 2013, as part of its Fine Jewellery Sale in London. Estimated to fetch between £1 million and £1.5 million, the "Trombino" ring by renowned Italian jeweller Bulgari realised more than four times its high estimate, selling to Laurence Graff of Graff Diamonds for £6.2 million. This record price of US$1.8m per carat beat the previous world record price of US$1.68m per carat for a blue diamond.

The diamond is a "fancy deep-blue" stone weighing 5.3 carats.

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