GENEVA—An exceptionally-large blue diamond sold yesterday for 48.6 million Swiss francs ($48.5 million)—a new record price for any jewel at auction, Sotheby’s said.
It culminated two Geneva auctions in which a convicted Hong Kong tycoon on both times bought a rare coloured diamond to honour his daughter.
The 12.03-carat “Blue Moon” diamond, set in a ring, was said to be among the largest-known fancy vivid blue diamonds and was the showpiece gem at the Sotheby’s jewellery auction.
A packed room broke into applause after the hammer came down at a price of 43.2 million Swiss francs, excluding fees—within the pre-auction estimate range of about 34-54 million francs.
The “Blue Moon”—so-called in reference to its rarity, playing off the expression “once in a blue moon”—topped the previous record of $46.2 million set five years ago by the Graff Pink, Sotheby’s said.
The diamond also set a new record of more than $4 million per carat—capping the day-long, high-end jewellery sale that reaped roughly $140 million.
On its Twitter account, Sotheby’s said the jewel was purchased by a Hong Kong private collector and promptly was renamed “The Blue Moon of Josephine”—a similar name to one given to a pink diamond ring that sold for $28.5 million at Christie’s in Geneva a day earlier (“Sweet Josephine”).
The auction house didn’t identify the buyer but in both cases it was Hong Kong billionaire Joseph Lau, his office said today.
“Yes, the two diamonds are bought by Joseph Lau,” said a secretary from his office who didn’t identify herself.
At a Sotheby’s Geneva auction in 2009, Lau bought another blue diamond, paying a then-record $9.5 million for the 7.03 carat “Star of Josephine.”
The gem reportedly was named after the youngest of his five children.
Lau is a property developer with a fortune estimated by Forbes at $9.8 billion.
The polished blue gem was cut from a 29.6-carat diamond discovered last year in South Africa’s Cullinan mine, which also yielded the 530-carat “Star of Africa” blue diamond that is part of the British crown jewels.
The Smithsonian Institution’s “Blue Heart” also was discovered there in 1908.
Sotheby’s said experts took five months for an “intense study” of the original “Blue Moon” diamond, and a master cutter took another three months to craft, cut, and polish the stone.
Blue diamonds are formed when boron is mixed with carbon when the gem is created.