With only a 100 pieces made, the Endeavour Chinese Calendar Limited Edition timepiece by H. Moser & Cie—developed in partnership with Agenhor SA—is deceptively clever and a feat in ingenuity. Despite its complexity and high ambition, it looks effortlessly elegant. A technical marvel, the timepiece combines the Chinese lunisolar calendar with the Gregorian calendar in a fine balancing act. Displaying the 12 signs of the Chinese animal zodiac alongside moon phases on one side and solar phases on the other, it’s the perfect gift for any watch collector in the region, as we’re just months shy of the Year of the Dragon.

Edouard Meylan, CEO of H. Moser & Cie, explains that the “synergy between our two partner companies gave rise to the Endeavour Chinese Calendar Limited Edition, which conveys the complexity of the Chinese calendar and encapsulates it in an elegant and refined watch that is easy to use, read, and adjust.” Meylan highlights the “minimalist and elegant aesthetics” of the timepiece, and the “contemporary Westernised interpretation of Chinese traditional culture, unlike the other models of its kind available on the market, which are extremely complex in functional display, difficult to read, and have a very oriental design.”

“While the Gregorian calendar is exclusively solar, the Chinese calendar is primarily lunar, as it tracks the cycles of the moon,” the brand explains. Several Asian cultures use heavenly bodies to calculate cycles based on the sun, moon, or both, so the timepiece’s lunisolar calendar is not only aesthetically pleasing but also technically challenging. 

Symbolising the union of two different cultures and measurements and their blissful co-existence on a watch face, the Endeavour Chinese Calendar Limited Edition does the rare feat of uniting the elements of the solar and lunar calendars, calculated separately but synchronised with meticulous precision. If it sounds complicated, it’s not—there’s a reader-friendly aesthetic that makes the piece easy to operate and elegant to hold and behold.

Historically, it has been notoriously difficult to produce a true Chinese perpetual calendar in a mechanical watch as the cycles do not repeat in the same way as a Gregorian calendar, so the strategic partnership with Agenhor SA, an independent atelier that conceptualises, develops, and creates innovative complications, was key to this horological collaboration. H. Moser & Cie and Agenhor SA put their heads together to craft a timepiece that is “able to precisely indicate all the lunisolar calendar information for every 12 years without any corrections.”

H. Moser & Cie explains that “other Chinese calendars on the market require at least 70 manual corrections over a duodecimal period [but] this is the first movement to operate according to the same cycle without external intervention.” All of this is rendered possible by “two cams that work in parallel and convey information on the number and duration of Chinese months using feelers” which help to calculate the Chinese lunisolar months, years, corresponding zodiacs, moon phases, and dates of the Gregorian calendar until its next service in 12 years, which is when the cams will be exchanged for another 12-year cycle.

In trying to comprehend the Chinese calendar algorithm, one can travel through thousands of years of history and appreciate its subtleties, complexities, symbolism, and lunisolar rhythm. Understanding the seasonal change was imperative to those who depended on agriculture to survive, so the lunar calendar has its roots in the observation of nature, permitting one to follow the perpetual cycles of the lunisolar terms and four seasons that were so essential to farming. By adapting this circuitous and ancient Chinese system for calculating time, an exercise rarely tackled by a luxury Swiss watchmaker, the Endeavour Chinese Calendar Limited Edition is H. Moser & Cie’s tribute to the traditions of the East in a timely way.

All the functional and technical details aside, the appearance and aesthetics are just as eye-catching. Set in a 40 mm red-gold case, the midnight-blue fumé dial subtly reveals the H. Moser & Cie logo in transparent lacquer. Crescent-shaped windows display the pertinent day, month, and moon-phase information, while a window at 12 o’clock indicates the year and animal zodiac, and the Gregorian calendar details sit at 6 o’clock.

H. Moser & Cie’s Endeavour Chinese Calendar Limited Edition timepiece is priced at CHF 68,800 (HK$599,970) and be reserved here.