Sotheby’s plans to auction a blue diamond that it estimates is currently worth 35 million US dollars francs (AU$48.8 million), which would break the record for a stone of that hue.
Weighing 12.03 carats, the blue diamond termed internally flawless by the GIA with the highest possible colour grade of fancy vivid blue could sell for a record US$55 million when put on the block at a Nov. 11 jewelry auction in Geneva, Sotheby’s said in a statement Thursday.
The gem, called the “Blue Moon,” was polished out of a 29.62-carat rough diamond found by Petra Diamonds Ltd. last year at the Cullinan mine in South Africa. Cora International, a New York-based gemcutter, purchased the diamond and took more than six months to prepare the stone.
Blue diamonds are formed when boron mixes with carbon when the gem is formed. Sotheby’s set the record for highest price for a blue diamond in auction when it sold the 9.75-carat “Zoe Diamond” for US$32.6 million in New York in November 2014.
Dubbed the Blue Moon diamond, the buzzworthy stone will tour Hong Kong, London and New York before hitting the auction block in Geneva on November 11.
“The Blue Moon diamond is a simply sensational stone of perfect colour and purity,” David Bennett, head of Sotheby’s international jewellery division, said in a statement
Blue Moon is the largest cushion-shaped stone graded as a fancy vivid blue diamond to ever appear at auction. The GIA Monograph notes the singularity of the gem’s spectacular blue, which “could be indescribable to even the most experienced diamantaire or colour theorist; some, however, liken it to the ocean”.
If the higher end of the US$35-$55 million estimate is achieved, the Blue Moon would be a diamond record-setter. But it would need to outperform the Graff Pink sold in November 2010. That 24.78 carats pink diamond brought just over US$46 million.
In November 2014, a 9.75 carat blue diamond fetched US$32.6 million at auction, setting the current record for the category.
Diamond specialists Cora International bought the uncut Blue Moon last year for a reported US$26 million. “The fact that you could buy it rough, plan it and cut it is special,” said Suzette Gomes, CEO of Cora International to Forbes. “This is a billion years old and it’s going to be here long after we’re gone. That’s the beauty of diamonds.”
The estimate for the Blue Moon is subject to change depending on exchange rates, Sotheby’s said.