Emerald-cut white diamond
A model displays an emerald-cut white diamond, set as a ring, during an auction preview at Sotheby's in Geneva on May 5, 2010. Reuters/Valentin Flauraud

A rare 100-carat emerald-cut white diamond will be auctioned in New York on April 21 and Sotheby’s estimates that the pre-sale price of the stone is between $19 million and $25 million, the Associated Press reported. According to Sotheby’s, the stone is the only classic emerald-cut white diamond of the highest quality to ever come to auction.

The diamond was mined in the southern part of Africa and had weighed more than 200 carats, the AP reported, adding that the gem has a flawless D color and is considered “perfect.” Only five “perfect” diamonds have reportedly been auctioned in the last 25 years.

In 2013, a 118-carat oval-cut stone was auctioned at Sotheby’s for $30.6 million. The sale was a record for a white diamond.

In 2010, a 24.78-carat pink diamond was auctioned for $46 million at Sotheby’s, setting the record for any diamond sold until now, AP reported.