A 7.59 carat, internally flawless, fancy vivid blue diamond is displayed at Sotheby's auction house in New York September 4, 2013. The Premier Blue, the world's largest round fancy blue diamond ever ... more 
A 7.59 carat, internally flawless, fancy vivid blue diamond is displayed at Sotheby's auction house in New York September 4, 2013. The Premier Blue, the world's largest round fancy blue diamond ever graded by the Gemological Institute of America, is expected to sell for as much as $19 million during an auction in Hong Kong in October. REUTERS/Brendan McDermid (UNITED STATES - Tags: SOCIETY WEALTH BUSINESS) less 
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Reuters | Photo By BRENDAN MCDERMID / REUTERS
Wed, Sep 4, 2013 5:49 PM EDT