A moon phase watch is not unusual, there are lots. What is unusual about the Jaeger-LeCoultre Rendez-Vous Moon is that the moon phase has as an extraordinary degree of accuracy. A normal moon phase watch approximates the actual average duration of the lunar month, 29.530587981 days, to 29.5 days, by means of a wheel with 59 teeth (driving a disc with two moons) that is advanced once every 24 hours. This may seem close enough, and it would mean having to readjust the moon phase display by one day every two years and seven and a half months. But watchmaking is a constant quest for perfection, and by adding more gears with more teeth, it is possible to increase the precision. This watch is accurate to one day in 972 years. Compare this to IWC’s Portugieser Perpetual Calendar Double Moon, accurate to one day every 577 years.
The other unusual thing is that this is a watch for women, with a graceful and quirky design with its stylized hours arc with elongated numerals, and generous diamond-setting. The moon phase display itself is large, in mother-of-pearl. The other significant feature of the watch is the star that can be adjusted by the second crown at 2 o’clock. The user can set it to a time important to her, the rendez-vous of the watch’s name, a very poetic touch. The other crown at 4 o’clock is used to adjust time and moon phase.
The watch is in two sizes, 36 mm and 39 mm, with blue satin strap. The two watches look similar, but there are some subtle differences. The 36-mm version has a dial with blue numerals and 166 brilliant-cut diamonds. The 39-mm version has a guilloché-crafted dial coated in blue lacquer, enhanced by 208 brilliant-cut diamonds.
Both watches are powered by the Jaeger-LeCoultre automatic Calibre 935 movement, with 43 hours’ power reserve. The case is in white gold.
Price and availability
The 36-mm version of the Jaeger-LeCoultre Rendez-Vous Moon, reference Q3523490, costs €42,500; the 39-mm version, reference Q3533490, costs €52,000. They will be available in boutiques in about September-October 2015.
Below, the 39-mm version:
Below, the 36-mm version: