Rotonde de Cartier Astrocalendaire is designed like an amphitheatre, with the intention of clarifying the perpetual calendar’s indications. (Photo Laziz Hamani © Cartier 2013)

Again, we’re looking ahead to fantastic timepieces being presented at this year’s Salon International de la Haute Horlogerie (SIHH), thanks to brands such as Cartier, who has released several new additions to its Fine Watchmaking collection, the Rotonde de Cartier Astrocalendaire eing one of them.

Before we dive into the details of this exceptional timepiece, you have to know that the Fine Watchmaking collection is Cartier’s way to approach haute horlogerie , a constant research, supported by technical expertise with a drive that redefines and questions watchmaking conventions by reinventing traditional complications.

Rotonde de Cartier Astrocalendaire’s (Photo Laziz Hamani © Cartier 2013)

The Rotonde de Cartier Astrocalendaire represents a new vision of the perpetual calendar thanks to the creativity of its design and its amphitheatre-style display.

It overcomes numerous readability issues that are specific to the traditional approach to this complication, which requires the juxtaposition of twelve months, seven days, the date and the type of year in a diameter of just a few centimetres.

Arranged three-dimensionally in concentric levels, the display of the perpetual calendar’s functions is spread over the different levels: the day is indicated on the first. It is followed by the month on the second, which is itself surmounted by the date. Thin windows move along these tiers. The perpetual calendar’s final function is indicated by a hand located on the back of watch and shows what type of year it is: a leap year or a normal year.

The see-trough back of the Rotonde de Cartier Astrocalendaire watch showing the self-winding calibre 9459 MC. Please note the leap year indicator on the right. (Photo Laziz Hamani © Cartier 2013)

The design of the movement

Consisting of gear trains, the construction of the Rotonde de Cartier Astrocalendaire watch’s movement is a watchmaking feat that solves all the functional and ergonomic problems connected with this type of complication. It breaks away from the design of traditional perpetual calendars and introduces an alternative that enables any risk of breakage to be anticipated, adjustment errors to be resolved and chronometry to be improved.

Anticipating risk of breakage

Partially patented, the gear train system of the Rotonde de Cartier Astrocalendaire’s 9459 MC movement replaces the traditional lever and spring mechanisms with a gear train mechanism that substantially limits the risk of breakage when the watch is over-wound at inadvisable times. The traditional design of a perpetual calendar prohibits any manual correction several hours before and after midnight at the risk of breaking the mechanism. The adjustments made using four minuscule push-pieces on the side of the case are impractical and never clearly identified.

Simplified setting using the crown

This operating problem no longer exists with the Rotonde de Cartier Astrocalendaire watch’s movement thanks to a setting system that uses the crown.

In addition to the traditional setting of the hour and minute, the crown also controls the date and month indicators.

This ease of use is further increased by the possibility of correcting the functions both forwards and backwards. Wearers of the Rotonde de Cartier Astrocalendaire watch need no longer fear going beyond the current date as this error is easily corrected.

Masterful chronometry

The Rotonde de Cartier Astrocalendaire watch houses at its heart a flying tourbillon: a complication that is emblematic of the Fine Watchmaking collection.

Certified “Poinçon de Genève”

The Rotonde de Cartier Astrocalendaire watch is certified “Poinçon de Genève”, in accordance with the new regulations’ requirements. The self-winding calibre 9459 MC is assembled and adjusted in the new Cartier Fine Watchmaking workshops located in the heart of Geneva, upstairs from the Cartier boutique on the rue de Rhône. Its finishes were carried out according to the standards of the most prestigious watchmaking certification.

Combining watchmaking innovation and technical creativity, the Rotonde de Cartier Astrocalendaire watch follows in the footsteps of the Rotonde de Cartier Astrorégulateur and Rotonde de Cartier Astrotourbillon watches, thus taking its place as a major complication in Cartier’s repertoire of watchmaking craftsmanship.

Technical specifications

Rotonde de Cartier Astrocalendaire watch
Tourbillon complication, perpetual calendar with circular display, calibre 9459 MC “Poinçon de Genève” certified timepiece

Case: platinum

Diameter: 45 mm

Crown: beaded in platinum, set with a blue sapphire cabochon

Crystal: sapphire

Case back: sapphire

Dial: silver-coloured Bezel: platinum

Hands: sword-shaped blued-steel

Casing-up diameter: 45 mm

Case thickness: 15.1 mm

Strap: black alligator-skin

Clasp: double adjustable folding buckle in 18-carat white gold

Water-resistance: 30 metres / 3 bar / 100 feet

Movement: Manufacture mechanical with automatic winding, calibre 9459 MC, tourbillon and perpetual calendar with circular display, “Poinçon de Genève” certified timepiece

Casing-up diameter: 14 lines, i.e. 31.38 mm

Total diameter: 32 mm

Thickness: 8.1 mm

Number of jewels: 51

Number of parts: 382

Balance: 21,600 vibrations/hour

Power reserve: approx. 50 hours

Limited series of 100 numbered pieces.