Biggest Orange Diamond May Fetch $20 Million at Auction

A pear-shaped, vivid orange diamond could fetch as much as $20 million, or $1.3 million per carat, at Christie’s next month.

The auction house will offer the 14.82-carat stone, the largest known orange diamond in the world, in its Geneva sale on Nov. 12. The following day, Sotheby’s will auction a vivid pink diamond valued at more than $60 million.

The last time an orange diamond of the same classifications appeared at auction, it weighed 5.54 carats. Known as “The Pumpkin Diamond,” it fetched $1.3 million at Sotheby’s in 1997, selling to Ronald Winston, a son of the Harry Winston founder.

Christie’s diamond has been with the same anonymous owner for at least 30 years, the auction house said, describing its clarity as VS1.

“It’s very, very good, but it has natural imperfections,” said Alan Bronstein, a consultant in colored diamonds, who knows the stone.

While pink and blue diamonds regularly appear at auctions, the orange stones are much rarer.

“As far as orange diamonds go, it has no peer,” Bronstein said. “It’s unpredictable what a diamond like that can go for. We are entering uncharted waters.”

The most expensive diamond at auction fetched 45.4 million francs ($45.6 million) at Sotheby’s in Geneva in 2010; the fancy, intense pink stone weighed 24.78 carats and was snapped up by jeweler Laurence Graff.

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