This pear-shaped colourless diamond is expected to sell for about $20 million (R184m) at an auction in Switzerland in May.
The D-colour flawless stone, weighing 101.73 carats, will feature in a jewellery auction by Christie’s International at the Four Seasons Hotel des Bergues in Geneva, on May 15.
It is the largest colourless diamond of this optimum grade to appear at auction and is being sold by a client who wishes to remain anonymous.
This was the first time the gem had appeared for sale and the buyer would be able to name it, the London-based company said this week.
The stone was recently cut from a 236-carat rough diamond found at the Jwaneng mine in Botswana.
It took 21 months to polish, Christie’s said.
Demand for the rarest diamonds as an alternative asset and portable store of value has pushed up prices in recent years.
The Jwaneng (meaning “Place of small stones”) open-pit diamond mine, the world’s richest by value, is jointly owned by De Beers and the government of Botswana.
At the top end of the market, white stones are regarded as less desirable than their even rarer coloured equivalents.
The record price for any gem at auction is the Sf45.4m (R438m at this week’s exchange rates) paid by London dealer Laurence Graff for a 24.78 carat emerald-cut fancy intense pink gem at Sotheby’s in Geneva, in November 2010.
The record auction price for a colourless stone is the Sf20.4m ($21.5 million at the time) with fees paid for the 76.02 carat Archduke Joseph diamond at Christie’s in Geneva, in November. – Bloomberg