True Moon Ref. 1TMAS.U03A.C42B

The True Moon timepiece features the world's first mechanism capable of providing a realistic view of the phases of the moon as we see them in the northern hemisphere with a deviation of just one day in 125 years. This unprecedented feat was achieved by using the synodic month of 29 days, 12 hours and 44 minutes - the time between successive recurrences of the same phase - as a basis for calculation. 

The moon phase display at 6 o'clock is set by a pusher integrated in the case at 10 and has 18 revolving discs, each bearing a true representation of the current phase of the moon. The 19 diamond stars on the dial depict the Big Dipper, Small Dipper and Cassiopeia. The watch has an engraved relief of the earth on a faceplate at 12 o'clock and a date display at 3 o'clock.


Ref. 1TMAS.U03A.C42B
Stainless Steel Case


hours, minutes, centre seconds, perpetual moon phase at 6 o'clock, date display at 3 o'clock


Exclusive Arnold & Son mechanical movement, self-winding, 21 jewels, diameter 38.6 mm, thickness 7.47 mm, power reserve 42 h, 28'800 vibrations /h, perpetual moon cycle at 6 o'clock. Movement decoration: rhodium treated with fine circular graining and 'Côtes de Genève'.


Stainless Steel,
diameter 46mm, cambered sapphire with anti-reflective coating on both sides, case back metallic sapphire


Blue dial. Engraved earth at 12 o'clock. 19 diamonds, yellow stars. Rhodiated indexes, polished. Rhodiated facetted hands, polished.  


Hand stitched blue alligator leather 


50 m

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