‘The Enigma,’ a 555-Carat Black Diamond, Could Sell for $6M at Auction
The massive natural fancy black diamond will be offered without reserve at Sotheby’s next month.

In February, Sotheby’s will put “The Enigma” up on the block. Weighing 555.55 carats, Sotheby’s said it is the largest faceted diamond of any kind to ever appear at auction.
The Engima is being sold without reserve, meaning there is no minimum bid required to win the stone, though the auction house said it believes the diamond could achieve £3 million-£5 million ($4.1 million-$6.8 million).
Both GIA and Gübelin issued reports for The Engima, identifying it as a natural fancy black diamond.
GIA’s library said natural fancy black diamonds have a Mohs hardness of 10, like other diamonds.
They owe their color to numerous minute dark crystals or clouds of graphite, magnetite, hematite, or native iron, it added, and because they have so many inclusions, black diamonds are difficult to polish.
The Enigma is a free-form faceted stone, both labs stated in their reports. Its shape is inspired by the hamsa, a palm-shaped symbol that is a sign of protection.
The hamsa is associated with the number five, reflected in the diamond’s 555.55 carats as well as its 55 facets.
In 2004, when it issued the grading report, GIA said The Enigma was “the largest fancy black, natural color and largest diamond” it had graded to date, and Gübelin said it was the largest faceted diamond it had examined to date.
The stone was also listed as the largest cut diamond in the world in the 2006 Guinness Book of World Records.
The diamond has never been seen on the market nor has it been exhibited to the public, but now “The Enigma” will take center stage as part of a dedicated online-only auction at Sotheby’s.
Sotheby’s unveiled the diamond Monday. It will be on view at the Dubai International Financial Centre from Jan. 17-20, after which it will travel to Los Angeles from Jan. 24-26 and then London from Feb. 2-9.
The one-lot auction will be open for online bidding from Feb. 3-9.
Sotheby’s will again accept cryptocurrency as payment, following the sale of the “10138 The Key” for a record $12.3 million via cryptocurrency last year in Hong Kong.
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