555-Carat ‘Enigma’ Black Diamond Sells for $4.3M Via Cryptocurrency
The founder of a cryptocurrency company purchased the stone and will rename it the “Hex.com” diamond.

Richard Heart, founder of cryptocurrency company Hex, tweeted Wednesday that he’s the one who purchased the diamond. He said he will rename the stone the “Hex.com” diamond.
Unsurprisingly, he used cryptocurrency to buy it, the auction house confirmed in a tweet of its own.
Sotheby’s offered the diamond in a one-lot sale that ran from Feb. 3-9, selling it without reserve, meaning there was no minimum bid required.
The final hammer price fell at the low end of the auction house’s pre-sale estimated range of £3 million-£5 million ($4.1 million-$6.8 million).
I won the world's largest cut diamond for our #HEXican cultural heritage! It'll be called the https://t.co/mLZsmWqXG0 diamond, it weighs 555.55 carats and has 55 facets. Congratulations to all you #HEXicans with #5555 club https://t.co/mLZsmWqXG0 tattoos. Let's all win together! pic.twitter.com/37mfTGbzMe
— Richard Heart ETH FORK PulseChain.com,PulseX.com!❁ (@RichardHeartWin) February 9, 2022
The hamsa, the palm-shaped symbol that is a sign of protection, inspired its shape. The hamsa is associated with the number five, aligning with the diamond’s 555.55 carats as well as its 55 facets.
In 2004, GIA issued a grading report for The Enigma, stating it was “the largest fancy black, natural color and largest diamond” it had graded to date.
The 2006 Guinness Book of World Records also listed it as the largest cut diamond in the world.
Prior to the Sotheby’s sale, the diamond had neither been seen on the market nor exhibited to the public.
The sale of the black diamond via cryptocurrency follows that of the “10138 The Key” flawless diamond in Hong Kong last year.
The buyer paid $12.3 million for the stone using the digital payment system.
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