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The World’s Thinnest Tourbillon, the New 2mm Piaget Altiplano Ultimate Concept Tourbillon (incl. Video)

Piaget takes the world record for tourbillon thinness back home, with a spectacular 2mm thin watch!

| By Xavier Markl | 5 min read |

One field of expertise immediately comes to mind when thinking about Piaget: the art of crafting ultra-thin watches. Throughout its history, the brand has become synonymous with legendary calibres, such as the 2mm thin 9P introduced in 1957 and the 2.3mm thin 12P micro-rotor movement unveiled in 1960. Approximately a decade ago, the groundbreaking 900P heralded a radical reengineering of watch architecture, seamlessly fusing the mainplate with the caseback. This innovation laid the groundwork for the creation of the Altiplano Ultimate Concept, unveiled in 2018 at a mere 2mm thickness, making it the thinnest mechanical watch ever produced at the time. As the brand celebrates its 150th anniversary in 2024, a milestone to mark that date was to be expected. The latest iteration of the AUC, the Altiplano Ultimate Concept Tourbillon, retains its remarkable 2mm profile, a hallmark of its predecessors. However, it now boasts the addition of a tourbillon, making it the thinnest tourbillon watch ever created.

To celebrate its 150th anniversary, Piaget had to go one step further than its Altiplano Ultimate Concept (AUC)… The tourbillon occupies a special place within the pantheon of complications, often regarded as the pinnacle of horological craftsmanship. With the Piaget Altiplano Ultimate Concept Tourbillon 150th Anniversary, it takes a whole new dimension – or not, considering it is paper-thin at just 2mm and looks almost two-dimensional. Holding it in your hands is surreal. And for the record, it is now the thinnest tourbillon watch ever, the previous record held by the Octo Finissimo Tourbillon Automatic at 3.95mm (housing the 1.95mm BVL 288 calibre).

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At first glance, there are many similarities between this new Altiplano Ultimate Concept Tourbillon and the 2018 AUC… But there is more than meets the eye. If some of the basic concepts have naturally been kept, 90% of the parts are new. Piaget did far more than merely add a tourbillon regulator to an existing movement.

Like the 900P and the first version of the AUC, the basic principle is still the radical reengineering of a watch’s architecture, which involves fusing the case and movement into a single component. In short, the “movement” components are directly integrated into recesses machined into the caseback instead of being stacked on a mainplate. The idea is to avoid having different layers in the watch architecture, taking advantage of the entire surface of the watch and rearranging and building all functions in the same horizontal plane.

The first challenge for Piaget’s watchmakers was to reimagine the tourbillon. Instead of a conventional construction where it is held by its underside, plus eventually with an upper bridge, the tourbillon cage is guided peripherally by ball bearings. From an aesthetic perspective, it also allowed incorporating a cool sapphire opening in the caseback. Beating at a 4Hz frequency, the balance wheel also rotates on ball bearings. It is slightly off-centred from the rotation axis of the cage. As expected, it features a flat hairspring and four gold adjustment weights. All in all, the tourbillon has dimensions of 14mm x 1.49mm. Last, to minimize its weight (0.37g in total), it is mainly made of titanium and steel where possible. 

Once the tourbillon was reimagined, the question was to cope with the 30% additional power required to drive the rotation of its cage while still delivering around 40 hours of power reserve (versus 44 hours for the 2018 Altiplano Ultimate Concept). First, it required a new made-to-measure barrel, slightly larger, fitted with a more powerful spring with a thicker blade. Then, just like the first version of the AUC, most of the gear train wheels are mounted on ball bearings to minimize friction while eliminating the need for bridges that would add an extra layer. The barrel itself has 96 tiny ceramic balls at its periphery.

Just like the first AUC, this technical feat requires trimming down the components to the limits of feasibility and working with the most extreme tolerances, eventually reimagining their architecture and function. For instance, the sapphire crystal is 0.2mm thick and has a diameter of 36.40mm, while the back sapphire crystal is 0.16mm x 12.52mm. 

The principle for the flat “telescopic” crown with its endless screw has been kept. A winding tool is provided to wind the watch smoothly. 

The Piaget Altiplano Ultimate Concept Tourbillon 150th Anniversary has a diameter of 41.5 mm, and its blue PVD-treated cobalt alloy case is water-resistant to 20 metres. Piaget also slightly reworked the aesthetics and the decorations, which were truly challenging to perform given the tight tolerances. For example, the wheels are now made with four arms instead of the six previously used; these are diamond polished and chamfered by hand, a very delicate process as you cannot deform them. The screw heads now have cross-slots. The captions on the barrel now appear in relief.

The Piaget Altiplano Ultimate Concept Tourbillon is worn on a calfskin leather strap fitted with an M64BC cobalt alloy pin buckle. Overall, the Altiplano Ultimate Concept is superb, and like these other rare watches at 2mm or less, it feels almost unreal to strap it around your wrist. Besides the captivating rotation of its tourbillon, it looks even better than the 2018 version, with numerous aesthetic upgrades. Of course, it is always interesting to list records for the books. Most importantly, the ingenuity needed to create these record-thin watches is just mesmerizing. The price of the watch is “upon request” but was not communicated to us when requested… to give you an idea, though, the Altiplano Ultimate Concept without a tourbillon was announced at EUR 420,000. 

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