Switzerland Auction Sothebys — A Sotheby’s employee displays the rare Blue Moon Diamond during a preview at Sotheby’s, in Geneva, Switzerland, Wednesday, Nov. 4, 2015. Keystone via AP

GENEVA, Switzerland—An exceptional 12.03-carat diamond dubbed “Blue Moon” was sold in Geneva for 48.6 million ($48.4 million, 40 million euros) Swiss francs on Wednesday, setting a new world record, auction house Sotheby’s said.

The vivid diamond, described as flawless by experts, was bought by a private collector from Hong Kong, who immediately renamed it “The Blue Moon of Josephine.”

The rock, set in a ring, went under the hammer for 43.2 million Swiss francs, with the final sale price amounting to 48.6 million Swiss francs including fees.

David Bennett, head of Sotheby’s international jewelery division, said the sale broke several records, making the gemstone “the most expensive diamond, regardless of color, and the most expensive jewel ever sold at auction.”

It also fetched the highest-ever price per carat, he said, with the buyer shelling out 4.02 million Swiss francs per carat.

Two bidders were locked in a telephone bidding war for eight minutes before the hammer went down, with the precious jewel staying within its pre-sale estimate of $35-55 million.

The diamond was discovered in South Africa in January last year and was the largest cushion-shaped blue stone in the fancy vivid category to ever appear at auction.

The record-breaking sale comes a day after rival auction house Christie’s sold a rare 16.08-carat pink diamond, the largest of its kind to ever appear at auction, for $28.5 million, narrowly beating pre-sale projections.

Experts say the market for colored diamonds has grown increasingly robust and both the blue and pink diamonds garnered a lot of attention in the run up to this week’s magnificent jewel sales in Geneva.