A "perfect" 100-carat diamond in a classic emerald cut sold for just over $22 million at auction on Tuesday.
The internally flawless D color stone is the only classic emerald-cut white diamond of the highest color and clarity and over 100 carats to come to auction, according to Sotheby's.
The final price on Tuesday night was $22,090,000, including the buyer's premium.
"This 100.20-carat diamond is the definition of perfection. The color is whiter than white. It is free of any internal imperfections," Sotheby's New York jewelry department head Gary Schuler said in a statement prior to the sale, likening its transparency "to a pool of icy water."
The presale estimate had been between $19 million and $25 million.
The diamond was mined in southern Africa within the last 10 years and weighed over 200 carats before it was cut and polished, the auction house said.
The seller wished to remain anonymous. The buyer was also anonymous, and the winning bid came in over the phone.
Only five "perfect" diamonds over 100 carats have sold at auction in the last 25 years, with a 118-carat oval-cut stone fetching $30.6 million at Sotheby's in 2013. It set a record for a white diamond.
The record for any jewel is $46 million for a 24.78-carat emerald-cut pink diamond, set at Sotheby's in 2010.