The "Pink Star" diamond has sold for a record-breaking $US71.17 million ($A94.29 million) at an auction in Hong Kong.
"The Pink Star was sought by three clients before selling to a bidder on the phone with our Asia CEO Kevin Ching," Sotheby's said on its Twitter account.
The sale of the 59.6-carat pink diamond was part of Sotheby's magnificent jewels and jadeite auction.
The oval mixed-cut pink diamond, roughly the size of a quail's egg, is the largest internally flawless fancy vivid pink diamond the Gemological Institute of America has ever graded, said Sotheby's.
"The extraordinary size of this 59.60-carat diamond, paired with its richness of colour, surpasses any known pink diamond recorded in history," said David Bennett, Worldwide Chairman of Sotheby's Jewellery Division in a statement.
The gem was mined by De Beers in 1999 and the 132.5 carat rough diamond was cut and polished over a period of two years by Steinmetz Diamonds.
The previous record for a pink diamond was held by the "Graff Pink," a 24.78-carat diamond that went for $US46.16 million dollars at Sotheby's Geneva in November 2010.
