Roger Dubuis loves to deal in excesses – over the years their brand of “hyper horology” involves extroverted case designs backed by some wildly inventive movements. The latest offering – Excalibur Superbia – is much in the same vein, its case is made from a white gold and palladium alloy and is set with 600, yes six hundred, white diamonds and blue sapphires that amount to 11 carats and features an updated version of their characteristic double flying tourbillion movement.

The case has 600 stones that amount to 11 carats

The Excalibur Superbia's creation was inspired by the work of Japanese artist Kaz Shirane. Widely acclaimed for his work in interior design, and spatial art, Shirane’s installation featuring  prism-shaped mirrors is echoed by the tetrahedron-shaped gems on the Excalibur Superbia. As far as visual aesthetics go, this has all the Excalibur family traits – the skeletonized dial, the star-shaped bridge, and the imposing tri-lug case are all familiar.

Chunky with a 45-mm diameter, the case is an alloy of white gold and palladium, a shiny white metal that’s rarer and more expensive now than gold. However, what make this watch truly stand out is the shape of the gems it uses. Every stone set on the flange, bezel, case, and crown is tetrahedron-shaped and assembled with an invisible setting on curved surfaces, an impossibly-difficult task for gem setters.

Each tetrahedron stone is a different set

Since the case has invisible setting (the mounts that hold the stones are not visible), the gem setter has to spend hours just preparing the case to receive the stones – so grooves and ridges have to made to hold each stone from the back. The raised pyramidal shape of each stone makes this a painstakingly laborious process – it requires extreme skills to set the stones into the case without risk of breakage.

It takes about 420 hours to set the case and bezel

The spangled case alone holds 238 stones, each a different shape. This complex arrangement means that the gem setter has to deal with the points of six or seven stones meeting simultaneously in the same spot. The entire process takes about three times longer than if the same case is set with baguette-cut stones. According to the brand, it takes 420 hours just to set the case and bezel. And we haven’t even talked about the grooving or the cutting of the stones.

A conceptual sketch of the Excalibur Superbia

The watch uses a new skeletonized movement, the RD108SQ – this an update on the RD105SQ, which was the first skeletonized movement with a double flying tourbillon connected with a differential. The two escapements oscillate at 3 Hz (21,600 vph) and the tourbillon cages are now made from titanium. The characteristic star-shaped bridge is set with diamonds and the double section flange of the open-worked dial is set with tetrahedron-cut diamonds and sapphires. The manual-winding movement has a power reserve of 72 hours and carries the prestigious Geneva Seal (Poinçon de Genève) which is visible on the shot-blasted grey NAC-coated movement bridge.

This is a one-off piece and is part of Roger Dubuis’ Unique series (which also features the Excalibur Diabolus in Machina minute repeater) that allows buyers to customize each watch to ensure exclusivity. The price? $858,500