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Sotheby’s, Crypto and a 555 carat ‘Space Diamond’

A 555.55 carat diamond, recorded in the Guinness World Records as the largest polished fancy black in existence, will be offered at a single-lot auction at Sotheby’s early next month. The online sale will be without reserve, meaning the highest bidder will win the diamond no matter the price.

Named “The Enigma,” the auction house expects it to sell for between $4.1 million and $6.8 million, given the hearty appetite bidders have had for gemstones in recent times.

555 carat black diamond
Photo credit: Sotheby’s


Sotheby’s broke new ground in July, 2021, when the auction house sold a 101.38 carat pear-shaped diamond, named “The Key” for $12.3 million in cryptocurrency. No other physical object approaching that value had ever been offered for sale accepting payment by cryptocurrency. “The Enigma” will arrive in London on February 2 via Los Angeles, January 24-25, after its launch in Dubai. Katia Nounou Boueiz, head of Sotheby’s UAE commented:

We are honored that Dubai has been chosen as the first stop for this exceptional rarity and are thrilled to play a part in its journey, which began so many millions of years ago… This is the first time we are introducing our cryptocurrency offering in the UAE, a move that is in line with the government’s own commitment to exploring new digital, technological, and scientific advances.

Katia Nounou Boueiz
Katia Nounou Boueiz (photo by Harpers Bazaar)

555.55 Carats / 55 Facets

The diamond was deliberately planned, cut and polished to resemble the Middle Eastern hamsa symbol, representing protection, fortune, and strength. The symbol is also associated with the number five. According to Sotheby’s it’s one of the toughest diamonds in existence (more about carbonado below), making the precise crafting of it’s 55 facets to a weight of precisely 555.55 carats a remarkable technical achievement, especially given the likelihood of its extraterrestrial nature.

Diamonds from Space

Black-diamonds, also known as carbonado, stand apart. They have more porosity than other diamonds and can also be somewhat harder. They are found in alluvial deposits in Brazil and Central Africa. Neither of those places are associated with kimberlite, the usual source of gem diamonds, which has made them – appropropriately – an enigma. A paper was published in the December 2006 edition of Astrophysical Journal Letters reporting the discovery of hydrogen trace elements in carbonado black diamonds. The details of that discovery imply that carbonado existed long before the Earth was born, arriving here from interstellar space.

Further speculation suggests that black diamonds may have been the product of supernova explosion. They started as diamonds the size of asteroids first, around a kilometer or more in diameter, and broke up while making Earthfall in the two countries where they are found today. Apart from the notoriety of some famous (and infamous) black diamonds throughout history, carbonado received relatively little attention from jewelry professionals prior to the year 2000. Mostly fragmentary, black-diamonds traded at low prices and were primarily used in industry.

Two decades later, The Enigma takes center stage.

555 carat black diamond
Photo credit: Sotheby’s

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