Let’s not be modest and expose some naked calibres! But to do this properly, they must first be perfectly protected. Hard, resistant, and scratchproof sapphire is the perfect bodyguard for a watch movement. Sapphire crystals are mainly used on the dial and on the caseback of a watch, but can also appear on other case components and on the movement itself to create the ultimate skeleton show.
Watchmaking at its Best
As surprising as it may seem, the Corum Golden Bridge movement is not a tightrope, but a watch movement. This fascinating calibre, with its linear gears, is suspended as it if it was being levitated between four sapphire walls. This mythical movement – patented by watchmaker Vincent Calabrese in 1977 – is credited with the revival of skeletonized watches. It was enough to take watchmaking into another dimension and it is no surprise that its creator is known as the “Engineering philosopher”.
Sapphire Boxes
Extremely hard, the synthetic sapphire used in watchmaking is practically scratchproof. Its robustness, however, makes it very difficult to work with. Watch cases and components made of sapphire crystal represent a real feat of machining. On the Rebellion Weap-One Diamond Asymmetrical Flying Tourbillon, for example, two sapphire nut-shaped crowns surround a cylindrical case, which is also made of sapphire. On the ends, two transparent rollers display the hours and minutes.
Unusual Tourbillons
What better way to highlight the show of a legendary mechanism designed to defy gravity than by adding transparency? The Rebellion Weap-One also has a flying, asymmetrical tourbillon that rotates on several axes. Corum’s Golden Bridge also comes in a tourbillon version of its suspended movement. At Jacob & Co., the company presents the most spectacular sapphire cases that highlight its three-axis tourbillons. One of the most eye-catching versions is the Jacob & Co. Astronomia Tourbillon Flawless Diamond.
For the Bovet Braveheart model, the Dimier Manufacture developed a flying tourbillon with a cage held by the middle of its axis for maximum visual lightness. Bovet is also an expert in beautifully designed movements that play with transparency. Both the bridges and three-quarter plates allow the lower section of the dials and the tourbillon to be fully revealed.
Variations on Transparency
Watchmakers love nothing more than to bring skeletons out of the closet. After all, skeletonization consists of showing as much as possible of a mechanism’s inner workings, which are usually hidden, or only visible through a sapphire caseback. To achieve this, as much metal as possible is removed from the plate and bridges of a watch in the most aesthetic way. For example, on the Piaget Polo Skeleton, the barrel spring, the oscillating weight, and all the movement’s components are visible from the front. This is a great way to constantly revise your knowledge of watchmaking mechanics.
Some watchmakers and designers choose to reveal part of the mechanism through open-worked elements, instead of skeletonizing the entire movement. One such watchmaker is Trilobe which offers an original off-centred display concept (developed by Jean-François Mojon) and gives a glimpse of the workings thanks to a “rosette” cut into the second’s ring. A discreet glance through this small window is enough to imagine the mechanical ballet behind the scene. After all, a picture is worth a thousand words!
