Sponsored by the Gemological Institute of America
Sotheby’s Is Selling This Perfect 102-Carat Diamond with No Reserve
Online bidding for the D flawless stone starts Sept. 15, with the live in-person auction set for early October in Hong Kong.

Hong Kong—This fall, a 102.39-carat D flawless diamond will go up for sale at Sotheby’s Hong Kong, with what the auction house describes as an “unprecedented twist” for these unusual times.
The oval-shaped stone has no reserve price and is being offered by the auction house without a pre-sale estimate, Quig Bruning, head of Sotheby’s jewelry department in New York, explained in a phone interview Wednesday.
A reserve price is the confidential minimum selling price agreed upon between the auction house and the consigner.
Bruning said sometimes, items are offered at auction without reserve—Bonhams, for example, is selling a collection of intaglios and cameos without reserve at a sale later this month—but there’s usually still an estimate given.
This stone will go up on the auction block without either, meaning the highest bid will be the winning bid.
“This is absolutely going to be a gauge of the market,” he said. “We are truly looking at, what will the market bear?”
Despite the toll COVID-19 has taken on the global economy and the havoc it’s wreaked on live events, Bruning said Sotheby’s has had success selling jewelry online and at the live auctions it has held this year.
He pointed to the fancy colored hearts sold in Hong Kong this summer as examples.
He said the auction house has confidence in the value of large, exceptional diamonds, and views it as an “ideal time” to offer this stone via a hybrid online-offline sale and “set the market.”
The 102.39-carat D flawless diamond has excellent polish and symmetry; Bruning called it “an extraordinary stone” that is “a beautiful example of a diamond.”
“It just transfixes anyone who looks at it,” he said. “There’s something above and beyond that this stone possesses. There’s a life and a character to it that you don’t normally see.”
Though Sotheby’s is not revealing the name of the company that consigned the diamond for sale, it did say Diacore cut and polished the stone over the course of a year from a rough diamond weighing 271 carats (pictured above) discovered at De Beers’ now-closed Victor Mine in Canada in 2018.
The auction house said it is one of only eight diamonds of “regular shape” (meaning modern cuts, not old mine, old European, etc.) that are over 100 carats and D color and flawless or internally flawless ever to be offered at auction.
Sold for between $11
The 102.39-carat stone is also the second-largest oval-shaped diamond of its kind to appear at auction, surpassed only by the 118.28-carat oval Sotheby’s sold for $30.8 million, or $260,252 per carat, in Hong Kong in 2013.

Sotheby’s will sell the diamond in a live single-lot auction in Hong Kong on Oct. 5.
Bruning said the auction house does plan to have bidders present at the auction—in addition to taking absentee, online and phone bids—though it will ultimately depend on the situation on the ground in Hong Kong at that time.
By-appointment-only previews are taking place in Beijing, Shanghai, New York and Taipei before the stone returns to Hong Kong for the sale.
Online bidding opens next Tuesday, Sept. 15.
The Latest

The 2025 Australian Open champion is the jewelry brand’s first athlete ambassador.

The West Village jewelry boutique’s new shop-in-shop is the cornerstone of Nordstrom’s revamped jewelry hall.

The Seymour & Evelyn Holtzman Bench Scholarship from Jewelers of America returns for a second year.

This past year, the manufacturer said it recorded below-zero emissions per carat of natural diamond.


The brand’s “Golden Strada” statement necklace features round, marquise, and pear diamonds that sparkle like Fourth of July fireworks.

JSA’s Scott Guginsky provided a list of nine security measures jewelers should observe while locking up for the long weekend.

The countdown is on for the JCK Las Vegas Show and JA is pulling out all the stops.

Located on Rodeo Drive, the store’s design was inspired by Hollywood and Los Angeles culture.

The new location continues the brand’s celebration of its 25th anniversary.

The online watch marketplace’s “Time Is Our Thing” campaign highlights the importance of time.

She will oversee strategic planning, fundraising, industry partnerships, and the launch of the Gem Legacy Campus in Tanzania.

Working with Amazon’s Counterfeit Crimes Unit and law enforcement, Pandora helped to shut down a large-scale counterfeit network in China.

The jewelry company has closed its three California brick-and-mortar stores, as well as its online shop, for now.

The company is providing the opportunity for an FIT student to work alongside master diamond cutter Willie Lopez in its workshop.

He is remembered for his successful entrepreneurship, generosity, and dedication to his family.

The jewelry store chain has reportedly been struggling with costs related to tariffs as well as tough retail competition.

Welcome warm summer days with red hot rubies perfectly chosen as July’s birthstone.

Co-founders Afzal Imram and Lin Ruiyin brought their son’s story of a cosmic egg, toadstool, and railroad to life in their new collection.

The best time to prepare for the holiday season is right now, according to columnist Emmanuel Raheb.

This year’s winner is Morgan Keefe, who is currently studying at GIA to be a gemologist.

“The Jewelry Book” comes out this September.

The company is focused on modernizing the custom jewelry buying experience with e-commerce tools like product visualization and 3D styling.

Following its recent acquisition, the storied brand has updated its leadership team and regional managers.

AGS also named the recipient of its “Women in Leadership” scholarship.

The 20-karat yellow gold and diamond wrap ring is modeled after the Monstera plants in the garden of the brand’s Miami villa.

Rocksbox President Allison Vigil shared the retailer’s expansion plans, and her thoughts on opening stores in malls.