This time last year, with little fanfare, Sotheby’s Diamonds opened the doors to its bijoux boutique on Bond Street. The jewellery found inside the intimate salon, however, was very much worthy of fanfare: from a range of one-off pieces featuring exceptional D-Flawless stones, to a collection of rare colored diamonds.
And to celebrate its one year anniversary, this morning Sotheby’s Diamonds revealed its most exceptional gem to date: a 102.34-carat, D-Flawless, Type IIA round brilliant diamond, which the auction house describes as “the rarest and most valuable white diamond ever to come to market”.
The stone bears the highest possible ratings in terms of colour (a D grade representing the purest, whitest hue), clarity (Flawless, meaning there are no internal or external blemishes even when viewed under a microscope) and cut, making it the largest such stone known to man. It’s also part of an ultra-rare subgroup of gem-quality diamonds known as Type IIA, signalling chemical purity and making it crystal-clear to the eye.
To date, only seven D-colour diamonds weighing more than 100 carats have ever appeared at auction, and none of them have been round brilliant cuts. Diamond cutters usually prefer to maximise the yield from a rough stone by producing a pear or emerald-cut stone.
The diamond was cut from a 425-carat rough mined by the De Beers group in Botswana. The cutting process took over six months and required the diamond to be transported between Johannesburg and New York. According to Patti Wong, founder and chairman of Sotheby’s Diamonds, the diamond cutter “approached the task with the precision of Michelangelo”.
The diamond is over 61 carats smaller than the stone that currently holds the title of the world’s most expensive D-Flawless diamond: the 163.41-carat emerald-cut held within the De Grisogono necklace that sold for $33.7 million in Geneva last November. Of course, that price included a not-inconsiderable amount of emeralds and further diamonds within the rest of the necklace.
Despite its smaller size, due to its exceptional quality and rarity, the brilliant-cut diamond is “expected to greatly exceed” the current world-record price, according to a Sotheby’s Diamonds representative. The diamond will not be auctioned but will be sold privately by Sotheby’s Diamonds, which also has boutiques in New York and Hong Kong, and as such the exact price tag is being kept under wraps.
“In the course of my long career, which has brought me close to some of the greatest stones the earth has ever yielded, I have not encountered anything quite like this,” says Wong.
“With its outstanding weight, its perfect colour, clarity and cut, it is a masterpiece of nature brought to life by human hand, blazing with a brilliant firework-like display of almost every colour on the spectrum – mesmerising to behold. It is a huge privilege to mark the first anniversary of our London salon with the exhibition of such a superlative stone.”
While Sotheby’s Diamonds is hoping that the brilliant-cut will take the title of the world’s most expensive white diamond, the value of colourless stones pales in comparison to that of rare fancy coloured diamonds. The record for the most expensive diamond of any colour belongs to the CTF Pink, the 59.60-carat pink diamond that sold for $71.2 million at Sotheby’s Hong Kong last April.