Geneva — (CNN) An extremely rare 15.38 carat pear-shaped pink diamond — called the ‘Unique Pink’ — sold for $31.6 million at Sotheby’s in Geneva on Tuesday, making it the most expensive fancy vivid pink diamond ever to sell at auction.

The spectacular diamond, set in a simple ring, sold to an Asian private buyer who bid for the rare gem over the telephone. A Sotheby’s spokesperson said they were not yet able to reveal the buyer’s identity.

“It is difficult to imagine a diamond that better illustrates the term vivid pink than this outstanding stone…the color is simply astonishing,” David Bennett, worldwide chairman of Sotheby’s International Jewellery, said in a statement announcing the sale.

Sparkling record breakers

The most expensive pink diamond ever to sell at auction remains the 24.78 carat ‘Graff Pink,’ which sold for $46.2 million at Sotheby’s in November 2010.

However, yesterday’s ‘Unique Pink’ sale eclipsed the previous record for a fancy vivid pink diamond, set by the ‘Sweet Josephine’ at a Christie’s auction in November 2015.

That 16.08 carat diamond sold for $28.5 million to Hong Kong billionaire, Joseph Lau, who purchased it for his then 7-year-old daughter, Josephine.

As colorful as these diamonds may be, they pale in comparison to the diamond Lau purchased for his daughter at a Sotheby’s auction the very next day.

That 12.03 carat blue sparkler, dubbed the “Blue Moon of Josephine”, sold for an eye-watering $48.4 million, making it the world’s most expensive diamond ever.

But that record may soon be challenged, with the 14.62 carat ‘Oppenheimer Blue’ — the world’s largest vivid blue diamond ever to be sold at auction — going under the hammer at a Christie’s auction in Geneva on Wednesday night.

The-CNN-Wire ™ & © 2016 Cable News Network, Inc., a Time Warner Company. All rights reserved. (PHOTO: Sotheby’s)