Above: A Lange & Söhne Grand Lange 1 Moon Phase in pink gold

Combining an off-centre dial, outsize date and a lavishly-finished manufacture calibre, the Grand Lange 1 Moon Phase features all of the iconic hallmarks of A Lange & Söhne’s most famous timepiece family. The considerable 72-hour power reserve was achieved with only one mainspring barrel. This is why the height of the movement is a scant 4.7 millimetres. The case in yellow gold, pink gold or platinum has a diameter of 41.0 millimetres. Endowed with a classic screw balance, a balance spring developed and manufactured in-house, a three-quarter plate made of untreated German silver, and lavishly hand-decorated movement parts, the Lange manufacture Calibre L095.3 unites all of the classic features that connoisseurs have come to expect of an A Lange & Söhne timepiece. 

The moon phase display indicates the time that elapses from new moon to new moon with an accuracy of 99.9978 per cent. The average synodic month lasts 29 days, 12 hours, 44 minutes, and 3 seconds. For the sake of simplicity, most classic moon phase displays round this cycle down to 29.5 days. The resulting deviation of 44 minutes and 3 seconds per lunation adds up to one day in merely two and a half years. The much more precisely calculated seven-gear transmission of the Grand Lange 1 Moon Phase reduces the deviation per cycle to less than one minute. Once correctly set, and assuming that the watch runs continuously, the display would only have to be corrected by one day every 122.6 years. But just in case, the display can be adjusted at any time by using the push-piece embedded in the case flank between 7 and 8 o’clock, for instance if the watch has not been wound up for a longer period of time.

Above: Calibre L095.3 features a patented coating process which gives the moon disc an incomparably rich colour

The effort invested in the coating of the solid gold lunar disc exemplifies the degree of perfection to which Lange’s product developers are committed. Their goal was to depict the nocturnal sky as magnificently as possible. The result of their intensive research and development work is a patented coating process, which, with its incomparably brilliant colours and crisp texture details, fulfils even the most ambitious aesthetic expectations. Interference effects – the superposition of waves – eliminate all non-blue hues of light falling on the watch. This creates an intense blue tone for the eye of the observer. A laser is used to cut out more than 300 stars of different sizes with extremely sharp contours, producing a miniaturised image of the galaxy.