Within the plush splendour of Dior’s new boutique on Avenue Montaigne in Paris, with its haute couture salon and pâtisserie, is a not so hidden gem. Nestled in a display cabinet sits a fancy yellow cushion-shaped diamond named “Le Montaigne”. It has been cut to weigh precisely 88.88 carats to reference the founding of Dior on October 8, 1946 in the 8th arrondissement in Paris, and the “8-shaped” line — in French, “En Huit” — which together with the “Corolle” established the house’s vaunted New Look style.

Le Montaigne is destined to be a one-of-a-kind stone, which the house’s artistic director of jewellery, Victoire de Castellane, will set in a specially designed jewel. The use of a particular, or even a proprietary, cut is a practice gathering momentum among luxury houses seeking to strengthen their individuality and presence in the jewellery world, and to cater to clients’ desire for something special.

In 2001 Bucherer, in partnership with Dutch diamond cutters Royal Asscher, pioneered the trend with the introduction of its own Royal Asscher Cut, which improves the light reflection of the classic square-shaped cut by adding 16 new facets. In 2019, to celebrate its 100th anniversary, Italian house Buccellati debuted the Buccellati Cut, a square-cut diamond with 57 facets dented with rounded edges to mimic the house logo. “My goal was to have a stone that could perfectly combine with our style in jewellery,” says creative director Andrea Buccellati.

Last year, Chanel presented a 55.55-carat diamond cut in the octagonal shape of the Chanel No 5 perfume bottle stopper, and Chaumet debuted the sparkling, 88-facet Taille Impératrice cut inspired by “the hexagonal shape [of] the heart of [our bestselling] Bee My Love collection design”, explains Chaumet chief executive Jean-Marc Mansvelt. The number eight refers to the movements bees use to communicate among themselves — and in Chinese culture is considered lucky. Louis Vuitton, too, has its own diamond cuts: a rounded-cut flower and a pointed-cut flower modelled after its monogram.

Fresh out of a mine, a diamond resembles a dirty piece of glass, and is cut to sparkle. In their simplest form, diamonds are cut as octahedrons, or two pyramids with their bases connected.

Slicing the top off of the pyramids resulted in the first “table cut”, which appeared around the 15th century, with nine faces and improved fire (ability of gems to split light into colours of the spectrum). More facets led to more sparkle — and demand.

“From 1919 on, the round brilliant cut has largely been the dominant diamond cutting style, something that is reinforced when considering how diamonds are priced — one list for round diamonds, another for every other shape,” says Quig Bruning, head of the jewellery department at Sotheby’s Americas. He refers to the ultra popular round-shaped cut with 58 facets designed by Polish-Belgian mathematician Marcel Tolkowsky, who was born into a family of gem-cutters.

“Eighty-five per cent of all diamonds bought around the world are white round brilliant cut diamonds. The remaining 15 per cent are the traditional fancy cuts such as baguette, princess, oval, emerald, and so on,” says Vishal P Mehta, co-chief executive at Dimexon, a diamond cutter based in India.

According to Mehta, custom cuts such as those lately patented by luxury houses “generate talk-ability rather than bolstering sales”. But he stresses the importance of cutting when it comes to the overall value: “The quality of the cut is an important criterion. A better quality cut with better proportions, polish and symmetry may result in a smaller diamond but will potentially be more valued,” he explains.

Establishing a new diamond cut takes time. “Customers are sensitive to diamonds’ commercial value on the secondary market,” says Mansvelt, hinting at lower prices fetched by unusual cuts at auctions.

Yet the enthusiastic reception of the new Taille Impératrice by some of his house’s best customers, as reported by Chaumet’s Mansvelt, suggests a growing desire for unique cuts, which mirrors the rising interest in large, uncut stones and the more widespread appetite for one-of-a-kind pieces within the luxury sphere.

After all, the most famous diamonds are usually uniquely cut — think of the Koh-i-Noor owned by the British Crown or the Tiffany Diamond cut into a magnificent 128.54-carat stone worn by Audrey Hepburn, Lady Gaga and Beyoncé.

“Each facet of a diamond has a huge impact on its appearance,” says Bruning of Sotheby’s. “Creating a proprietary cut can be a compelling way of distinguishing your brand in a very busy marketplace.”

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