There is a new and unlikely ally for watchmakers engaged in the ceaseless quest for ever bigger wow factors in watch design – sapphire crystal. It is mostly taken for granted as the all-but-invisible “glass” layer protecting a glorious dial or, with a sapphire caseback, the intricacies of the movement. But with demand for new design fuelling the luxury watch market, creatives have recently begun to examine every material used in timepieces for their design potential and found that sapphire crystal has surprisingly versatile qualities.
It can be less than the thickness of a human hair and so fragile it would shatter unless set in a special way, as in Piaget’s ultra-thin Altiplano Ultimate Concept watch. It can be a solid block carved like a faceted jewel to make the inner workings of a watch visible from every angle – an effect employed spectacularly by Hublot, Bell & Ross and Richard Mille. It can be a magically invisible part of the structure, such as a bridge, allowing components of the movement to appear behind it; or a transparent subdial with delicate numerals, like the large seconds dial on Jaquet Droz’s new Skelet-One (£26,500), which reveals the skeleton movement.
Such pieces are not easy to create. Sapphire is the second hardest gemstone and virtually scratchproof, which is why synthetic sapphire has long been used for “invisible” discs, but making a case in it is difficult, time-consuming and costly – Mille’s initial models, six years ago, came in at well over £1m – and depends on specialist suppliers and evolving technology. Hublot’s CEO Ricardo Guadalupe says, “It has taken 20 years and several million Swiss francs’ worth of machinery to develop a way of making crystal components other than the glass at an acceptable cost.” Such watches are distinctly niche, and easily seen as boys’ toys, except that women also love their airy lightness, the way they reveal the movement’s secrets, and their sheer, unexpected beauty. As yet, relatively few brands make watches using sapphire crystal in imaginative ways specifically for women, which lends the models that do exist significant cachet. There are, in addition, an increasing number of designs that are technically unisex, but light and slim enough to appeal strongly to women.
Groundbreaking change often comes from outsiders, untrammelled by the rules of tradition. The first mystery clock (£45,000) – where the hands appear to float in space but are mounted on sapphire-crystal hour and minute discs, with the works in the perimeter and base of the piece – was made in the mid-19th century by French watchmaker turned magician Houdin (from whom Harry Houdini took his name). Starting in 1912, Cartier used the idea for highly prized objets d’art, jewelled fantasies in carved gold, platinum and hardstone, with the sapphire crystal discs inserted into citrine or rock crystal. It still makes them: unique pieces taking many months, and they appreciate – the record, $515,000, was paid five years ago for a diamond, gold, black onyx, enamel and rock crystal model once owned by Consuelo Vanderbilt Earl.
Horologists began to explore the use of sapphire-crystal technology in wristwatches in the late-20th century, notably Corum, whose 1980 Golden Bridge movement was suspended in a slender tonneau-shaped, gold-edged, sapphire-crystal case; its latest version (£77,500) is a round 39mm-diameter design with three layers of crystal, plus gem-set details. Sapphire disc specialist Quinting also began to release “mystery” watches in the early 1980s and Dior worked with the company on a six-disc model shimmering with coloured metallic flecks. Also at Dior, in 2005, John Galliano created the cool Christal design with pyramidal studs of sapphire crystal on bracelet and bezel. It still forms the basis of the popular Dior VIII range, although the studded bracelet is now in ceramic or steel. Dior continues its crystal innovation with the one-off Grand Bal Jardins Imaginaires (£210,000), where complex gem-set, marquetry and feathered dials are matched by sapphire backs, each with a unique tracery of gold butterfly-wing patterns made by a metallisation process.
Houses with a history in jewellery have also been adventurous. Cartier’s Révélation d’une Panthère (£96,500) is new and irresistible: the dark dial (best in green) contains a little heap of gold beads that, as your wrist moves, revolves into a panther head that mesmerisingly disappears and reappears like a very ritzy child’s puzzle. It works using an invisible system of channels in the sapphire crystal and a secret regulating fluid, and took five years and two patents to achieve.
Meanwhile, Piaget’s Altiplano concept mechanical model is so new it is not yet in production. “The reaction at this year’s Salon International de la Haute Horlogerie in Geneva was so strong from both men and women – the Altiplano range sells 50/50 – that we are working to commercialise it soon,” says senior watch specialist Quentin Hebert. “The problem is not cutting the crystal to 0.2mm but inserting it in the case. Once fixed by a special method it cannot break. It will flex with pressure, but is supported by the bridges that are below the crystal but above the hands and movement.” All this in a watch a record-breaking 2mm thick.
Boucheron reflects its high-jewellery heritage with the Épure Tourbillon Damier Cabochon (£184,000), which has a pavé-diamond dial in an apparent geometrical marquetry pattern – an optical illusion created by inserting above the dial an invisible sapphire-crystal disc hand-lacquered with a grid of black “cabochons” so that it mimics a chequered floor (the dial is too small to create this effect without sleight of hand). Dolce & Gabbana, on the other hand, references its high jewellery with the new Sofia (£5,450), a perfectly plain, square, rose-gold model where the sapphire crystal – its domed cut allowing complex facets reminiscent of a diamond – is the main feature. Top-quality crystal creates dancing light reflections and the retro-modern style is named after actress Sophia Loren.
The current pinnacle of crystal watch craft is the full sapphire case. Richard Mille designed his first women’s model, the RM 07-02 Pink Lady (from £883,000), in 2014 and describes its creation as “a hellish job, requiring the growing of crystals under high pressure and heat over several months, and when you introduce colour you can never be sure of consistency so the rejection rate is high. Also, sapphire’s hardness means milling the case takes about 800 hours.” He takes great pride in the final creation, which he calls “a complete work of art – the delicately tinted transparency complements the rose-gold movement and all the details of the interior, including the diamond setting, are designed to be pleasing to the eye.” After four years, he has perfected a new, equally gorgeous, blue-tinted version (£1.1m) for the EMEA market.
For its Big Bang One Click Sapphire (from £44,000), Hublot has also taken on the challenge not only of making a female-friendly 39mm clear sapphire case, but of creating pale-pink and blue sapphire crystal cases (the tints coming from a mix of aluminium and titanium oxides and iron oxide). The clear Sapphire Rainbow version (£61,000) features a bezel of coloured baguette gemstones. Bell & Ross’s modern skeleton BR-X2 (£62,000) is an elegantly thin 8.85mm and has an ingenious construction: the movement’s held between two plates of crystal, fixed with the brand’s signature corner screws.
These watches, many with ingenious internal workings revealed to the eye, captivate, says Mille, because “the more you look, the more you see, every day for years to come” – the perfect basis for a lifetime’s relationship.