On looks alone, the new see-through Bell & Ross BR-X2 Tourbillon Micro-Rotor is a marvel – the visual allure of sapphire cases and tourbillons attracts as much as their technical complexity. Sapphire cases are much-loved because they expose all of a watch’s inner workings – a fascination unmatched in the world of mechanics – while the tourbillon ranks among the most skilled of horological feats.

Sapphire is tough enough to manage when producing the round discs that cover watch dials (crystals), but an entire case requires expertise on another level: cracking and chipping are just some of the hazards – which is why these high-level designs tend to be limited collection only. Creating a tourbillon – an extra function in the movement that rotates like a whirlwind as a means of defeating the effects of gravity – is complex in a whole other way.

Bell & Ross has experience of both, so it combined the two in its signature BR0 series with a couple of clever solutions to create the BR-X2 Tourbillon Micro-Rotor. The “sandwich” case construction allows for an entire sapphire case, with a micro-rotor to wind the watch that saves space. A metal plate containing the BR-CAL.380 automatic movement is captured by the see-through top-and-bottom solid sapphire plates, forming the sandwich and bolstering the 42.5mm case’s physical integrity. The movement itself is further skeletonised, and the watch is deceptively slim, with a case thickness of only 8.9mm.

The price tag – €59,000 – is a further surprise. Watch mavens will tell you that is a deliriously low sum for a tourbillon in a sapphire case. All of which points to the clear skill of the Bell & Ross design team – because the BR-X2 looks like a million dollars.