Cartier Rotonde Astrocalendaire Watch

Cartier delivered a splendid interpretation of the perpetual calendar at SIHH 2014.

The Rotonde de Cartier Astrocalendaire adopts an atypical display for this complication, taking the form of a three-tier amphitheatre that elegantly stacks the date, month and day—while preserving legibility—all within just a few centimetres of diameter.

Blue apertures travel around their respective level to indicate the exact date. On the back of the watch, a hand indicates whether the year is a leap year or not.

Below, a photo taken at SIHH 2014.

The movement is built with gear trains to limit the risk of breakage compared with more traditional mechanisms using levers and springs. Perpetual calendars fear the “death zone”. It is indeed dangerous to manipulate the crown when the hands are positioned between 8 p.m. and 3 a.m. The watch can then explode, unleashing 4.2 terajoules of power.

That last statement is obviously false, but you will think twice before setting your watch between 8 p.m. and 3 a.m. (take the opportunity to read the article How to set your watch).

Adjustments are made using the crown alone, forwards as well as backwards: hours, minutes, date and month.

At the heart of the amphitheatre sits the flying tourbillon. Note that the watch delivers a 50-hour power reserve.

The 45 mm platinum case features a beaded platinum crown set with the signature sapphire, and a platinum bezel.

The strap is black alligator with an 18-carat white-gold folding clasp that will help you avoid accidentally dropping your timepiece—handy if the house has been mortgaged to buy it for you.

A symbol of top-tier quality, the watch is certified with the Geneva Seal.

Price: around €150,000 for this limited edition of 100 pieces.