Giant 100-carat diamond sells for $22.1M

100-carat diamond sells for $22M

A "perfect" 100-carat diamond sold for $22.1 million within three minutes of bidding starting on Tuesday evening, making it the most expensive colorless diamond ever auctioned in New York.

The large emerald-cut jewel was described as "an internally flawless, type IIa stone"—one of the purest and most valuable type of diamonds—and was the main attraction of the 370 lots on sale in Sotheby's "Magnificent Jewels" auction.

Ahead of the auction, the diamond was seen fetching between $19 million and $25 million.

The winning bidder took part in the auction via telephone and wanted to remain anonymous, Sotheby's said.

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According to the Sotheby's, only six "perfect" diamonds weighing over 100 carats have sold at auction in the last 25 years.

An employee holds the 100-Carat perfect diamond at Sotheby's auction house.
Leon Neal | AFP | Getty Images

"At this impressive scale, diamonds of this exceptional quality—D color and Internally Flawless clarity—are incredibly rare, and are considered 'perfect'," the auction house said in a press release on Tuesday.

"What distinguishes the present example within this rarefied league is its beautiful shape: it is the largest perfect diamond with a classic Emerald-cut ever to be offered and sold at auction. It also marks the first 100+ carat perfect diamond sold at auction in North America."

Lisa Hubbard, chairman of North and South America at Sotheby's International Jewelry Division, said the diamond was "exceptional in every sense of the word, and we were thrilled to see it achieve such a strong result."

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"The stone captivated people around the world throughout our extensive travels this spring, but it was a particular privilege to offer it at our New York headquarters."

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