The American jewelry house, founded by Latvian immigrants, has been creating American flag brooches since 1917.
Sotheby’s Finds 2 Partners for 60-Carat Pink Diamond
Diacore and Mellen Inc. have formed a partnership with the auction house to acquire an ownership interest in the 59.60-carat diamond known as the Pink Star.

Geneva--Diacore and Mellen Inc. have formed a partnership with Sotheby’s to acquire an ownership interest in the 59.60-carat Pink Star diamond.
“The three parties have formally partnered to achieve the value of the 59.60-carat stone, which Sotheby’s holds in its inventory,” the auction house said in a brief statement, declining to comment on the specific percentage of the stone owned by each entity.
The stone could be sold in the future, either privately or at auction, with proceeds split among the three companies per their ownership percentage, according to a Sotheby’s spokesman.
The stone is the largest internally flawless, fancy vivid pink diamond that the Gemological Institute of America has ever graded.
De Beers unearthed the 132.5-carat piece of rough that became the Pink Star in 1999 in South Africa.
Sotheby’s auctioned the polished diamond in November 2013, when it sold for $83.2 million, beating out the Graff Pink to become, at the time, the most expensive gemstone ever sold at auction.
New York diamond cutter Isaac Wolf bought the diamond but, according to Forbes, he defaulted on the payment and the stone was put into Sotheby’s inventory. The auction house reportedly had to buy the Pink Star for $60 million, the price it guaranteed the original seller.
Diacor is a multinational company with interests ranging from manufacturing to retail, and specializes in the creation of large, fancy colored and rare stones.
The firm is responsible for cutting some of the world’s most famous diamonds, including the 203.04-carat De Beers Millennium Star; the Heart of Eternity, a 27.64-carat fancy vivid blue, heart-shaped diamond; and the Pink Star.
Mellen, a family-run organization based in New York, is one of the top sources for exceptional stones.
The Latest

The artwork celebrates the Atlanta jeweler’s legacy and symbolizes its commitment to supporting local artists and its community.

Its team can evaluate jewelry and watches, as well as luxury handbags, artwork, and collectibles.

Colored gemstones, artisan finishes, mixed metals, and meaningful details are shaping demand in bridal jewelry.

Falling oil prices were a factor in the slight month-over-month improvement.


The new offering comprises more than 120 bridal and engagement ring styles with natural and lab-grown diamonds.

The clock is part of the celebration for the soon-to-open Rolex headquarters on New York City’s Fifth Avenue.

DCA is preparing the next generation of professionals by supporting workforce development, leadership growth, and career advancement.

The public relations professional is remembered for her benevolent generosity and unwavering commitment to those around her.

The new watch commemorates Pokémon’s 30th anniversary.

The luxury retailer is now called Exemplar Luxury Group.

The “Lady” collection is a new take on old beauty standards with gemstone-adorned hair pins and combs, a compact mirror necklace, and more.

All active members who earned their credential or designation before Dec. 1, 2025, are required to recertify.

The new jewelry collection uses a colorful palette of onyx, malachite, tiger’s eye, mother-of-pearl, lapis, turquoise, and coral.

Lee Michaels Fine Jewelry is celebrating 30 years in the Ridgeland, Mississippi community.

Sean Milliner has joined the company.

Classes will begin in August at GIA’s new Canary Wharf location.

A ring set with “hogback” diamonds, an early stone cut dating to around the 16th century, sold for more than $20,000 at a U.K. auction.

The rainbow version of the ring, our Piece of the Week, features angel-cut, octahedral lab-grown sapphires designed to be worn as armor.

The new initiative donates a portion of the proceeds from select charms to charitable causes.

The Brooklyn-based jeweler created a limited-edition version of its “Aura” eternity band, set with gemstones in the team’s colors.

Dallow will lead the International Colored Gemstone Association, effective July 6.

Senior Editor Lenore Fedow headed to Savannah to learn more about the 10-year, $10 million partnership between JM and the art school.

Its new capsule jewelry collection features gold-finished stainless steel pieces designed for a maximalist look without a luxury price tag.

The week-long event in Geneva is slated for April 2027.

The three industry leaders bring financial, communications, and legal expertise to the nonprofit’s board of directors.

Jewelers are missing out by not offering this one key add-on at the online point of sale, Emmanuel Raheb writes.























