‘Rarest of the Rare’ Blue Diamond Expected to Top $48M at Auction
The 15.10-carat fancy vivid blue, mined by Petra last spring and purchased by De Beers and Diacore, heads to Sotheby’s in April.

Sotheby’s announced Wednesday it will offer the 15-carat fancy vivid “De Beers Cullinan Blue Diamond” in a single-lot sale this spring.
The diamond is estimated to sell for more than $48 million, or $3.2 million per carat.
Mining company Petra Diamonds uncovered the original rough, weighing 39.34 carats, at the Cullinan mine in April 2021.
De Beers Group and manufacturer Diacore International, a De Beers sightholder and master diamond cutter, purchased the stone for $40.2 million last July.
Since then, the companies have been analyzing, cutting and polishing the stone to bring the diamond that’s been dubbed the De Beers Cullinan Blue to life.
What emerged is an internally flawless 15.10-carat step-cut fancy vivid blue diamond Sotheby’s is calling the largest vivid blue diamond ever to appear at auction.
The GIA Monograph Report on the stone states: “Achieving a fancy vivid color grade in a step cut or emerald cut adds to the rarity, since most other fancy shapes intensify the body color more efficiently in the face-up position than step cuts. To achieve a fancy vivid grade with a step cut or emerald cut, the inherent bodycolor has to be stronger than virtually every other fancy shape.”
Sotheby’s will offer the diamond in a live single-lot auction in late April—tentatively April 27—anchoring Sotheby’s Hong Kong Luxury Week.
Prior to that, it will be showcased in a worldwide tour, starting in New York before traveling to London, Dubai, Shanghai, Beijing, Shenzhen, and Taipei.
“Blue diamonds of any kind are rare on the market, but this is the rarest of the rare; nothing of remotely similar caliber has appeared at auction in recent years. Hundreds of millions of years in the making, this extraordinary blue diamond is surely one of nature’s finest creations,” said Patti Wong, chairman of Sotheby’s Asia.
“Now brought to dazzling life by the hand of one of the world’s most skillful cutters, it is the ultimate masterpiece—as rare and desirable as the very greatest works of art. At a time of unprecedented demand for the finest, world-class, colored diamonds, we are incredibly excited to bring to the market what is sure to become one of the most celebrated gems in the world.”
According to Sotheby’s, only five blue diamonds weighing more than 10 carats have gone to auction before, with none exceeding 15 carats.
The world auction record for highest price per carat belongs to “The Blue Moon of Josephine,” a 12.03-carat internally flawless cushion-shaped fancy vivid blue diamond, which sold for $48.5 million, or about $4 million per carat, in November 2015.
The “Oppenheimer Blue,” a 14.62-carat fancy vivid blue step-cut diamond, sold for $57.5 million in May 2016, setting the record for the most expensive jewel sold at auction.
The 59.60-carat “Pink Star” diamond later eclipsed the Oppenheimer Blue, selling for $71.2 million in April 2017. It remains the most expensive jewel ever sold at auction.
The Latest

Five of the 10 fastest-appreciating Rolex models on Bob’s Watches were Datejust 31 or Lady Datejust watches.

The Sherwood family and AJS Creations CEO Tejas Shah purchased the jewelry chain back from Palladium Equity Partners.

“The Elizabeth Taylor Collection” uses lab-grown diamonds and gemstones in contemporary designs inspired by the icon.

Experience gemstones with greater precision and comfort than ever before.

The artist wore Dana Rebecca Designs’ marquise diamond-set gold hoops at the Chiefs game last Sunday. Now they’re our Piece of the Week.


JSA and Jewelers Mutual shared advice on spotting suspicious behavior, combatting cell phone jammers, and staying safe at home.

Submit your pieces for a chance to win in this year's competition.

“Secret Language of Victorian Jewelry” unveils the meaning behind the symbols, motifs, and gemstones used in Victorian-era jewelry.

KIRAJewels.one gives retailers access to more than 500 SKUs of lab-grown diamond rings, earrings, necklaces, and bracelets.

This holiday season, look to pieces that will help to fill out customers’ everyday diamond jewelry wardrobe, experts say.

The Natural Diamond Council is now The Diamond Collective and has announced a new strategy under CEO Amber Pepper.

Paul’s Jewelers sells coffee, chocolate, and cookies from a custom gold-wrapped trailer parked outside the store starting at 7 a.m.

Part of its brand relaunch, the marketing around the campaign includes a contest involving a jacket set with 550 diamonds.

The curation, opening soon at the Crystal Bridges Museum of American Art, honors the jeweler’s heritage through a distinctly American lens.

The jewelry giant has partnered with the famed makeup artist to create a colorful new collection of charms and rings.

The association will mark the milestone at its convention next month.

The jeweler donated school supplies to Memphis, Tennessee, students during the event combining basketball and mentorship.

A federal judge denied Pandora’s motion to dismiss Foundrae’s claim for copyright infringement of its medallions.

People aren’t thinking rationally when they are buying luxury products, and we shouldn’t be selling them that way, Peter Smith writes.

The Baltimore Business Journal recognized the entrepreneur for her leadership in business and the jewelry industry.

The facility is located within SEEPZ and is GCAL by Sarine’s second location in India, joining its existing grading lab in Surat.

The four-day show is slated for Nov. 19-22 at the Metropolitan Pavilion in New York City’s Chelsea neighborhood.

Bernstein-Gulla has been working in the jewelry industry for 40 years, most recently as chief engagement officer for Hill & Co.

The relocated Glendale store, now at The Americana at Brand, was designed to be a contemporary “timepiece haven” inspired by luxury resorts.

The top lot of the auction house’s Hong Kong jewelry sale was an Art Deco Mauboussin necklace with ruby beads, which sold for $2 million.

Retailers and manufacturers headed to the Capitol this week to discuss tariff exemptions for diamonds and gemstones, among other issues.

























