Corum Bubble watches

The Corum Bubble is built around one idea: a sapphire crystal so steeply domed that it dominates the watch. Severin Wunderman conceived it in 2000, the year he bought Corum, taking as his inspiration the Rolex Deep Sea Special, an experimental dive watch of 1960. The original came in three sizes and ran until the end of the decade, and the Bubble returned in 2015 after a five-year break.

The 2015 revival is slightly larger than the original. Its 47 mm case stands 18.8 mm high, 8 mm of that being crystal, which magnifies the centre of the dial and distorts the edges. Short, curved lugs keep it comfortable for the size. Inside is Corum's automatic CO 0082, based on the ETA 2892. The launch pieces were two editions of 350 in PVD-coated steel, the Bubble All Black and the bronze-toned Bubble Vintage, alongside a non-limited Bubble Skeleton.

From there the Bubble became a canvas. The 47 mm models carry graphic dials in runs of 88: casino chips, roulette, dice, an 8 ball, python skin, the Joker, the Lunar System and its Death Star variant, and Luminova dials, with the Op Art Drop and Op Art Sphere² limited to 350. The 42 mm Bubble, 16.5 mm thick, repeats several of those themes and adds mother-of-pearl dials in blue, pink and white, some with a diamond bezel and rose gold. In 2016 Corum ran a contest inviting entrants to upload their own image for the dial.

The Big Bubble Magical goes further: a 52 mm titanium case, 20.2 mm thick and in some versions PVD-coated, with dials by artists such as Matt Barnes, Nelson de la Nuez and Elisabetta Fantone, each in a run of 88. The edition made with former footballer Djibril Cissé has a gold skull on a black dial and no hands: two red circles track the hours and minutes on an off-centre display on the flange, driven by the automatic CO 390 with 65 hours of power reserve. A 47 mm Big Bubble Magical also exists.