Since releasing its first full-sapphire case in 2012, Richard Mille has continued to push the boundaries of what’s possible with the gemstone in watchmaking. The brand’s new RM 75-01 Flying Tourbillon Sapphire is a culmination of this journey thus far, combining years of technical development and mastery with a new aesthetic twist.
Three versions of the RM 75-01 Flying Tourbillon Sapphire have been created, with all being limited editions. The first, which comes in a run of just 15 pieces, has a fully colourless sapphire case. The remaining two, with coloured casebacks, are limited to 10 pieces each: one in lilac pink, and the other in sapphire blue.
Cécile Guenat, director of development and creation at Richard Mille, says the colour palette was largely inspired by different aspects of the ocean. “Being able to use sapphire in multiple colours offered the opportunity to create multiple identities,” says Guenat, whose goal was to remind wearers of everything from waves to the deep sea.
Structurally, the Richard Mille team took a modern take on Gothic architecture to achieve a cathedral-like look in the RM 75-01 Flying Tourbillon Sapphire.
“These inspirations,” says Guenat of the dual sources, “provided us with a path guiding our choices of colours and the style we wanted for these pieces. Our goal was to distil the essence of these influences to offer a contemporary interpretation.”
As light shines through its transparent facets, the case evokes stained glass. The flange, meanwhile, mimics a dome and vaulted arches, sitting atop satin-polished titanium columns to form a ribbed vault, as though caressing a wonderful treasure within.
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A new movement
That treasure, it turns out, is the new calibre RM 75-01.
It took Richard Mille four years to develop the manual-winding movement with a flying tourbillon at 6 o’clock. The complication, which gives the impression that the tourbillon is suspended midair, is a result of there being no upper bridge on the mechanism’s case.
Taking advantage of negative space, the deliberate removal of frills in the movement’s inner workings enhances its visual appeal, striking a balance between clean, bold and intricate all at once.
The skeletonised baseplate and bridges have been rendered in grade-5 titanium with 5N gold and grey PVD treatment. Composed of 90% titanium with 6% aluminium and 4% vanadium, grade-5 titanium has high corrosion resistance and rigidity, a plus point for the watch’s durability and functionality.
Guenat says her team wasn’t “spontaneously attracted to a two-colour treatment for the metallic components”, but they wanted to highlight the various components within the calibre RM 75-01, especially given the transparent sapphire case. “When a movement is entirely crafted in 5N gold, you cannot properly distinguish its constituents,” she explains. “The creative team always begins by modelling the architecture before bringing out its depths using various materials and treatments.”
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Completing the calibre RM 75-01 are touches of pellucid sapphire, microblasted satin coatings and rhodium-treated wheels, which add touches of contrast to the movement’s overall appearance.
The flying tourbillon is complemented by a flying barrel at 12 o’clock, which similarly is left without an upper bridge. Completing a revolution once every 5.2 hours, this element regulates power delivery and enhances the watch’s performance.
Overall, the calibre RM 75-01 measures 29.71mm by 20.78mm, with a thickness of 5.45mm. The movement runs at a frequency of 3 Hertz and has a power reserve of about 65 hours.
Creating sapphire cases
Zooming back out to the RM 75-01 Flying Tourbillon Sapphire, the tripartite case measures 46.75mm by 32.9mm, at 14.35mm thick. It’s also water-resistant to 30m, thanks to two nitrile O-ring seals. Holding the case components together are 24 grade-5 titanium spline screws and 316L stainless steel washers.
Richard Mille works with the Swiss company Stettler to synthesise sapphires using the Kyropoulos method. Aluminium oxide, the compound from which the crystals are made, is heated to between 2,000°C and 2,050°C; over several weeks, the synthetic sapphire then grows around a seed crystal. This process allows for the synthesis of bigger, higher-quality crystals that can be used in Richard Mille’s watches; it also allows the brand to create new colours of sapphire by introducing different additives at specific points in time.
Minor hiccups, from variations in temperature or uneven crystallisation speeds, can cause irregularities in the final sapphires. Ensuring uniformity is also key so that the final cases are consistent in colour.
The room for error when working with sapphire is minuscule — literally. Sapphire, which ranks at a 9 on the Mohs scale of hardness, can tolerate only micrometres of variance during cutting and assembly. This means that even after the synthesis is complete, it takes 1,000 hours, including 40 days of polishing, to craft each block into the three parts of a case: bezel, caseband and caseback.
This technical complexity and challenging production process reinforce the RM 75-01 Flying Tourbillon Sapphire’s standing as an outcome of exemplary engineering.
On the face of it
The sapphire case may allow you to examine its inner workings from all angles, but, as with all timepieces, it’s ultimately the front of the watch that matters most. Continuing the theme of letting light through, the hands have been skeletonised. On the 5N gold upper flange, polished and bead-blasted steel indexes are punctuated with touches of SuperLuminova, enhancing visibility in low-light conditions.
The 5N gold diamond-set crown combines a coloured rubber gasket with a precious stone: the colourless and lilac pink versions have a white agate, while the sapphire blue watch’s crown is topped with a pink opal.
The colourless RM 75-01 Flying Tourbillon Sapphire comes with a sea-green strap; the lilac pink version has a light pink one, and the sapphire blue model has a white strap. All are made of rubber, with a grade-5 titanium folding clasp.
The RM75-01 Flying Tourbillon Sapphire emphasises Richard Mille’s mastery of sapphire in watchmaking. The interplay of colours, shapes and forms in each model advances the brand’s years-long experimentation with the gemstone, while maintaining its horological expertise in the calibre RM 75-01.
Some watches want to be seen. This one lets you look straight through — and that’s exactly the point.
