"Blue Moon" is expected to fetch up to $55 million when it goes under Sotheby's hammer on Nov. 11, in Geneva.
Sotheby's Mining News
After just three minutes of bidding, the final price was $22,090,000, including the buyer's premium.
The flawless, 100-carat diamond could fetch up to $25 million when it goes under Sotheby's hammer in New York on Tuesday
The gem, discovered a decade ago at one of De Beers mines in South Africa, is one of just five diamonds over 100 carats and of comparable quality to have been offered at an auction.
It has set a world auction record on a per-carat basis for a gem of this colour.
The diamond is expected to fetch between $12.8 million and $15.4 million at auction on October 7.
Flawless pink stone was expected to fetch $60 million.