A dazzling blue diamond once owned by mining magnate Philip Oppenheimer etched a record $50.6 million (S$68.7 million) at auction in Geneva Wednesday, auction house Christie's said.
The 14.62-carat "Oppenheimer Blue" is the largest stone in the exceptionally rare Fancy Vivid Blue category ever to go under the hammer, according to Christie's.
The anonymous buyer will have to part with a total of $57.54 million, all fees and commissions included, a Christie's spokesman said.
Before the auction experts ad said it was in with a chance of beating the record of $48.4 million set by Sotheby's in November with Hong Kong billionaire Joseph Lau's purchase of the 12.03-carat "Blue Moon of Josephine".
It did so after more than 20 minutes of bidding to become the most expensive polished diamond ever sold at auction, easily topping its pre-auction valuation of $38-45 million.
"This is the cut diamond and the jewel of all the record," a Christie's spokesman said after the auction attended by hundreds of people in a Geneva palace.
Sotheby's fetched a record price in the Fancy Vivid Pink Category on Tuesday, when a private buyer in Asia scooped up a 15.38-carat stone for $31.6 million.
Ehud Laniado, president of Cora International which sold the stone dubbed "Unique Pink", said he was "very happy with the sale price", and voiced confidence that the gem's value would rise over time.
"When you buy a Picasso, you pay a lot, but you know you are going to sell it for even more," Laniado told AFP.
Sotheby's also sold a blue diamond, weighing 7.32 carats, for $17.1 million.
A recent spate of eye-popping bids at Geneva's semi-annual magnificent jewel auctions has highlighted the surging value of precious stones, with some of the world's ultra-rich increasingly investing in hard assets as a safeguard against stock market volatility.
Britain's Sir Philip Oppenheimer (1911-1995) led a powerful cartel called the Central Selling Organisation for 45 years, tightly controlling roughly 80 per cent of the international diamond trade in a bid to prevent wild price swings.
Among his major credits was convincing the Soviet Union to sell its significant diamond reserves through his London-based cartel.
De Beers, the giant mining company built by the Oppenheimer family, also flourished in the latter half of the 20th Century, thanks in part to Sir Philip's outsized influence in the sector.
The blue stone has passed through several hands since Oppenheimer's death and Wednesday marked its first appearance at public auction.
"As a general rule, these stones are quite small," Christie's diamond expert Jean-Marc Lunel told AFP, noting that a Fancy Vivid Blue weighing just five carats typically generates considerable buzz in the diamond market.
Last week Canadian mining company Lucara Diamond on announced the sale of a huge 813-carat uncut diamond for a record $63 million (55 million euros).
The name of the buyer for the gem, which was discovered in Botswana, was not divulged, nor the conditions of the sale overseen by Nemesis International.
That record sale figure for a rough diamond is unlikely to last very long. Lucara is preparing to auction an even larger 1,109-carat diamond at Sotheby's in London on June 29.