A Fancy Vivid Blue pear-shaped diamond from the estate of Rachel “Bunny” Mellon brought $32.6 million on Thursday in Hong Kong. The price is an auction record for a blue diamond.

An anonymous Hong Kong collector won the 9.75-carat gem after a competition between seven bidders at Sotheby's.

With a pre-sale estimate of $10 million to $15 million, the platinum mounted diamond surpassed the previous record held by the Wittelsbach Diamond, a blue diamond that sold at Christie’s for $24.3 million in 2008.

The blue diamond sale comes after a $160 million auction of works earlier this month from Mellon's estate. She died in March at 103. Sotheby's is conducting a series of sales highlighting her well-known "eye."