This undated file photo provided by the Smithsonian Institution shows the 31.06-carat Wittelsbach-Graff Diamond. The fancy, deep grayish blue diamond, discovered in India in the 17th century and purchased by London-based jeweler Laurence Graff in 2008 for $24.3 million, is on display at the Museum of Natural History in New York from Thursday, Oct. 28, 2010, through Jan. 2, 2011. (AP Photo/Smithsonian Institution, File)