Our immediate reaction to a mysterious (transparent sapphire) element in a timepiece was and has always has been, really? Why? Yes, it does look mesmerizing when you can see through the mechanism, and yes there is an element of mystery behind it, but the real question is: Is it wearable? We had the pleasure of seeing the U20 Ultra-Skeleton tourbillon for the first time at Basel 2016 and woah! We were impressed!

Built like a supercar, the U20 Ultra-Skeleton tourbillon is streamlined and based on structural optimization. Made of sapphire, carbon and titanium, the U20 is at the forefront of cutting-edge watchmaking. From the movement to the case design, every aspect of the U20 has been conceptualized to allow light to enter the watch and reveal the splendor of the movement’s architecture and tourbillon. The first elements one sees are the raised dome sapphire crystal of the carbon case and the mirror-polished beveled edge of the monobloc titanium lugs, all reflecting the light.

A deeper look reveals the virtually transparent movement floating in the case and allowing an unobstructed view through the watch. The quest for transparency and three-dimensionality is essential in the world of ultimate high-end watchmaking. The goal for Angelus was to present the essence of the movement by removing any superfluous material. What seems to look deceptively simple to achieve requires great artistic vision and engineering prowess. The more material that is removed, the more the structure of the movement has to be carefully calculated to ensure rigidity and sturdiness.

The U20 Ultra-Skeleton even goes a step further. It does not boast an ordinary movement that has been skeletonized afterwards, but a tourbillon movement that has been created from scratch to be symmetrical, transparent and resplendent.

To further enhance transparency, the U20 features a sapphire main plate. The bridges are made of blued titanium and are skeletonized to increase transparency even further. The bridges’ beam shape also maximizes rigidity with the latter being essential for chronometric precision.

The discerning eye will be pleased to discover that haute horlogerie has not been sacrificed on the altar of transparency: components in the Ultra-Skeleton Tourbillon have been hand-chamfered, hand-polished and hand satin-finished to ensure that they look equally as good as their function.

And to further increase visibility into the top of the three-dimensional movement, the U20 Ultra-Skeleton Tourbillon features a unique design element. The case dispenses with a bezel and instead uses a sapphire crystal dome, which also allows a sideways view onto the movement.

The U20 Ultra-Skeleton Tourbillon deserves closer inspection, which reveals many of the well- thought-out details that go into transforming a skeleton watch into an ultra-skeleton haute horlogerie watch: the variable inertia balance wheel of the tourbillon is especially designed and crafted to minimize air friction; the sapphire main plate is polished to the highest optical grade; ruby bearings are set into solid gold chatons. The ultra-light case, entirely made of carbon-fiber, titanium and sapphire, has been designed to echo the visual lightness and the technical feel of the timepiece.

The sapphire in the U20 Ultra-Skeleton Tourbillon is very specific, offering the essential characteristics necessary for use in a haute horlogerie timepiece. The sapphire main plate is first crafted from a solid block of sapphire before being painstakingly polished to be perfectly transparent. This elaborate process results in a very precise main plate with tolerances in the micron range. The latter is important as the sapphire used throughout the Ultra-Skeleton Tourbillon is not decorative but 100% functional.

When worn it's incredible how one can easily forget having an ultra luxurious timepiece on the wrist. The titanium and carbon case, coupled with the titanium bridges, make for a feather light feel with a very comfortable rubber strap that hugs one's wrist quite nicely.

The U20 ULTRA-SKELETON TOURBILLON IS AVAILABLE IN A LIMITED EDITION OF 18 PIECES IN CARBON- FIBER/TITANIUM CASE AND priced at $69,950

THE U20 ULTRA-SKELETON TOURBILLON FROM ANGELUS