LONDON.- To celebrate the first anniversary of its New Bond Street salon, Sotheby’s Diamonds, a retail boutique specialising in the world’s finest diamonds, unveiled a stone of exception – an extraordinarily rare 102.34 carat white diamond. The stone is the only known round brilliant-cut diamond over 100 carats perfect according to every critical criterion: in addition to the high number of carats, the stone is also perfect in colour, clarity and cut.

At 102.34 carats, this masterpiece of nature is the rarest white diamond ever to come to the market and the largest, round D colour flawless diamond known to man. The only stone of its kind ever graded by the GIA (Gemological Institute of America), the diamond has achieved the highest rankings under each of the criteria by which the quality of a stone is judged (‘the four Cs’). The diamond is D colour (the highest grade for a white diamond); of exceptional clarity (it is completely flawless, both internally and externally), and has excellent cut, polish and symmetry. As with the famous Cullinan I and Koh-i-noor diamonds, which are part of the British Crown Jewels, the stone is part of the rare subgroup comprising less than 2% of all gem diamonds, known as Type IIa*. Diamonds in this group are the most chemically pure type of diamond and often have exceptional optical transparency.

Describing the stone, which is available for private purchase through Sotheby’s Diamonds and is on view to the public in Sotheby’s New Bond Street Galleries on 8 and 9 February 2018, Patti Wong, Founder and Chairman of Sotheby’s Diamonds, said: “This stone is over 100 carats of flawless perfection. 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. 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.”

A Rarity in the mythical world of 100-carat Diamonds
100 carats has always been a mythical number in the world of diamonds. While only a small number of diamonds weighing over 100 carats have been recorded, barely any diamonds of that weight are known to possess the same exceptional qualities of purity and perfection as the Sotheby’s diamond.

A Masterpiece of nature
Finding a rough diamond that allows the cutter to end up with a stone of over 100 carats is a true and very rare discovery. The 425-carat rough stone which yielded the Sotheby’s diamond was mined by De Beers in Bostwana and subsequently cut and polished, over a period of six intense months, by Diacore’s most experienced artisans, in Johannesburg and New York.

The Perfect Cut
The round shape is the most sought after shape for colourless diamonds as it gives the most light and life to the stone; the proportions are well defined to reflect the optimum fire and dispersion to the eye of the observer. When it comes to stones of significant size, it is very rare to find a round brilliant-cut stone, as the cutter will generally try to keep the maximum of weight from the rough; therefore elongated cushions, emerald-cuts, and pear-shapes are usually more common for large diamonds.

Given that diamonds are the hardest material on earth, great skill and precision is needed to cut them. Most of today’s greatest diamond cutters have learnt their trade from their forbears in an industry that – in spite of the advances of modern technology - still relies to a large degree on craftsmanship that has been handed down through families for generations. To cut a stone of this outstanding importance required a level of expertise and craftsmanship possessed by only a small handful of cutters. The Sotheby’s diamond is testament to the impeccable savoir-faire of the diamond cutter who, in the words of Patti Wong, “approached the task with the precision of Michelangelo”.