It’s the largest and most valuable blue diamond to ever come to auction.
And, it’s a recent discovery.
The De Beers Cullinan Blue diamond was mined in 2021 at South Africa’s Cullinan Mine, one of the few sources in the world for extremely rare blue diamonds.
Sotheby’s Senior Vice President and Sales Director for Jewelry Frank Everett said the jewel is remarkable on many levels.
“It’s rare because of the size. It’s over 15 carats. It’s a vivid blue. It’s internally flawless. And really one of the most rare aspects of it is the cut,” he said. “It’s a step cut, which really requires an exceptionally even saturation of color to achieve that beautiful step cut rather than a brilliant cut.”
The Gemological Institute of America (GIA) graded the diamond a Fancy Vivid Blue – the highest possible color grading according to Sotheby’s, awarded to no more than 1% of blue diamonds submitted to the GIA.
The De Beers Cullinan Blue will be offered in a single-lot auction at Sotheby’s Hong Kong this April and is estimated in excess of $48 million.
“This is the highest estimate ever for a blue diamond at auction, and that is simply because of the size,” Everett said. “There’s never been one so big.”
Blue diamonds at auction have had an admirable track record.
In 2014 the Mellon Blue Diamond, renamed ‘The Zoé Diamond’ at Sotheby’s New York, old for $32.6 million.
A year later, in 2015, Sotheby’s Geneva sold ‘The Blue Moon of Josephine’, a 12.03 carat cushion-shaped Internally Flawless Fancy Vivid Blue diamond for $48.5 million.
It still holds the price-per-carat auction record for any diamond or gemstone.