‘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.
The Latest

The new showcase dedicated to Italian jewelry design is set for Oct. 29-30.

Take a gaze at the sky with this pair of platinum diamond-set star earrings with blue lace agate drops.

In 2026, the jewelry retailer will celebrate a milestone only a small percentage of family-owned businesses survive to see.

You deserve to know what you are selling–to protect your customers as well as your business and your reputation.

Jeffrey Zimmer's decades of leadership at Reeds Jewelers are defined by integrity, a love of sourcing gemstones, and a heart for community.


The holiday catalog for 2025 features never-before-seen images of more than 100 one-of-a-kind masterpieces.

The brand has released a second installment of its collection of traditional and non-traditional commitment heirlooms.

The upcoming show provides savvy retailers with the opportunity to stock their cases with best sellers in advance of the holiday season.

Corey rescued New England chain Day’s Jewelers, preserving its legacy with strong people skills, pragmatism, and a “get-it-done” attitude.

Charles Robinson Shay was sentenced to life in prison plus 120 years while his accomplice, Michael James McCormack, got 75 years.

The Museum of Arts and Design's new exhibition features 75 pieces by the designer, best known for her work in the “Black Panther” films.

Timepieces at Luxury will take place at The Venetian and, like Luxury, will be invitation-only for the first two days.

As chairman of Schwanke-Kasten Jewelers, Tom Dixon has been tasked with honoring the past and shaping the future of the family-run store.

Katty Villapando Lyte and Mica Rencher received a $10,000 grant for their business, Shimmer Culture LLC.

The parents of the Dallas Mavericks rookie bought their engagement ring at a Day’s store in Bangor, Maine, in 1997.

The UK-based brand sourced the gemstones, which are fully traceable, from an artisanal mining community in Tanzania.

The trio of Advent calendars include a version with 18-karat gold and lab-grown diamond jewelry in a red lacquer jewelry box.

Created in collaboration with Nymphenburg Porcelain, the lock is part of a four-piece collection that took two years to bring to fruition.

Jewelry industry veteran Alisa Bunger has taken on the role.

The company and industry leader’s two-decade tenure with De Beers will come to a close at the end of the month.

“The Winter Egg” set the world auction record for a Fabergé piece twice at previous Christie’s sales.

The company will pay 1.5x silver’s current spot price for each pound of silver oxide batteries submitted.

The line includes a “Shadow” series crafted exclusively for the new men’s offering and reimagined styles from the brand’s core collections.

The rough on offer was recovered from a newer area at the Montepuez mine.

The retailer’s new collection of engagement rings and fashion jewelry is set with natural diamonds that are traceable via blockchain.

The champagne colorway in her newest “Ombré” collection combines white and trendy brown diamonds, a departure from her usual vibrant hues.

Kosann partnered with the Museum of Fine Arts, Boston, to create a set of necklaces inspired by the artwork on samurai sword handguards.