The "Pink Star", a huge flawless pink diamond, sold for 76.3 million Swiss francs (£51.75m, $83.02 million) including commission fees in Geneva on Wednesday (November 13), a world record price for a gemstone at auction, Sotheby's said.

The oval-shaped diamond, mounted on a ring, weighed in at 59.60 carats. It was bought by a man bidding in the room, who told reporters that he was buying it on behalf of an anonymous person whom he represented, and would not give his own name.

"Ladies and gentlemen, 68 million (Swiss francs) is the world record bid for a diamond ever bid and it's right here," Sotheby's David Bennett said to applause as he brought down the hammer in the Geneva salesroom.

The Pink Star was the star lot at Sotheby's semi-annual jewellery sale in Geneva, held in a heavily-guarded hotel showroom, which followed strong Hong Kong auctions last month.

"Of all the gemstones known, coloured - the rare pinks and blues and greens and so forth - are amongst the rarest of all stones and they're finally, I think, reaching the level as it were (where) the price is matching the rarity," said Bennett.

The previous record was held by the "Graff Pink", a 24.78 carat fancy intense pink diamond bought by Laurence Graff, the London-based jeweller known as "The King of Diamonds", in 2010 for 45.44 million Swiss francs ($45.75 million at the time).

The Pink Star was cut and polished from a 132.5 carat rough diamond mined by De Beers somewhere in Africa in 1999, according to Sotheby's, which said it had no information on the exact geographic origin.

It was first sold in 2007 and the seller wished to remain anonymous, a Sotheby's spokeswoman said.

Presented by Adam Justice

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