Sotheby’s auction house in New York is preparing to auction a 100.2ct D internally flawless emerald-cut diamonds at its Magnificent Jewels sale in April.
Described as the ‘Ultimate’ stone, it is one of only five diamonds of this size and quality ever auctioned.
Sotheby’s auction will take place on April 21, with this particular gem expected to fetch between $19m (£12.3m) and $25m (£16.1m).
Head of Sotheby’s jewellery department in New York, Gary Schuler, commented: “The color is whiter than white, it is free of any internal imperfections, and so transparent that I can only compare it to a pool of icy water.”
The original rough was greater than 200ct and was mined by De Beers in South Africa.