Rare 15-carat diamond sells for $31 million

Posted at 11:14 AM, May 18, 2016
and last updated 2016-05-18 11:14:18-04

It's not unusual for an auction house to call something unique. But Sotheby's latest diamond may be worth the $31.5 million it sold for Tuesday. 

Dubbed "The Unique Pink," it's the "largest fancy vivid pink pear-shaped diamond" ever auctioned, Sotheby's says

So how rare are we talking here? Sotheby's notes less than 0.002 percent of diamonds presented to the industry's top grading authority are pink.

And even fewer are over 15 carats. 

Still, the diamond sold for less than the top estimate of $38 million

And even that was far lower than the record for a pink diamond –– the "Graff Pink" 25-carat diamond sold in 2010 for $46.2 million. 

As of Wednesday morning, the buyer of "The Unique Pink" hadn't been named.  

This video includes images from Getty Images and clips from Sotheby's and the Gemological Institute of America Inc.