The Pink Star diamond has become the world's most expensive gemstone, selling at auction today for $71.2 million (£57.3 million) including buyer's premium. The 59.60-carat pink diamond is the largest Internally Flawless, Fancy Vivid pink diamond ever graded by the GIA, and sold for above its estimate of $60 million (£48.3 million) at Sotheby's in Hong Kong. It breaks the record previously held by the Oppenheimer Blue diamond, which sold for $57.5 million at Christie's in Geneva last May. It has also become the highest price item ever sold at auction in Asia.