Jewelry Judge Blog
September 15th, 2020
In an unprecedented move for a diamond of this importance and value, Sotheby's Hong Kong will place on the auction block an oval-cut, 102.39-carat, D-flawless diamond — without reserve. In auction parlance, that means the highest bid will be the winning bid, regardless of the amount or the intrinsic value of the stone itself.



No diamond of this caliber has ever been offered this way, according to Sotheby's. Typically, a high-value item would enter an auction with a reserve price, which is the confidential minimum selling price agreed upon between the auction house and the consigner. If the bidding fails to meet the reserve, the piece would be withdrawn from the sale.

“Offering without reserve is really a way to let the market decide what the price is going to be for this diamond,” Quig Bruning, Sotheby’s head of jewelry in New York, told barrons.com.

Online bidding starts today, Tuesday, Sept. 15, and the winning bidder will be determined during a unique, single-lot live event on October 5. Sotheby's did not publish a presale estimate for the diamond, but based on previous sales of similar stones, the winning bid may reach $30 million.

In 2013, a 118.28-carat, D-flawless, oval diamond fetched $30.8 million at Sotheby’s Hong Kong. That selling price translated to $260,252 per carat.

Sotheby's noted that this is the eighth time a D-flawless diamond weighing more than 100 carats has been offered at auction. It is only the second time in auction history that a 100-plus-carat D-flawless oval has hit the auction block.

The Gemological Institute of America described the stone as a Type IIa diamond with excellent polish and symmetry. Type IIa diamonds are colorless and chemically pure with no traces of nitrogen or boron impurities.



The 102.39-carat gem was cut by Diacore from a rough diamond weighing 271 carats. That stone was sourced in 2018 at De Beers’ Victor Mine in Ontario, Canada. The exacting process of cutting and polishing the diamond took more than a year, according to Sotheby's.

The Sotheby's headliner is scheduled to tour New York, Beijing and Shanghai before returning to the Hong Kong Convention and Exhibition Center from October 3-5.

Credits: Images courtesy of Sotheby's.