
An exceptional 12.03-carat perfect bule diamond will be on auction at Sotheby's Geneva Sale in November with an estimated price of 55 million U.S. dollars, the highest ever of its kind, the auction house said. (Xinhua/ AFP)

An exceptional 12.03-carat perfect bule diamond will be on auction at Sotheby's Geneva Sale in November with an estimated price of 55 million U.S. dollars, the highest ever of its kind, the auction house said. (Xinhua/ AFP)