Today, at the 2016 Salon International de la Haute Horlogerie in Geneva, the German watchmaker, A. Lange & Sohne, debuted the Grand Lange 1 Moon Phase “Lumen.” With the same dimension (41 mm by 9.5 mm) and movement (caliber L095.4) as the standard model, the watch is technically the same in most respects. The difference is the unique smoked sapphire crystal that makes up a portion of the dial, and that offers a view into the dial side of the movement. And, of course, the luminous hands, markers and outsized date indication.
The combination of the smoked dial and luminous material makes for a very distinctive and aggressive look, much like Grand Lange 1 “Lumen.”
In total, there are 446 components, including 45 jewels, and 7 screwed gold chatons, that make up the hand wound movement that powers this timepiece. The 3Hz (21,600 vph) movement can run for 72-hours autonomously on a full wind. The main plate and bridges are German silver, with Glashutte stripes on the top of the three-quarter plate bridge and perlage on the mainplate, including on the dial side, which is visible through the sapphire dial. Blued screws and a hand engraved balance bridge complete the high-end finish.
“Different from Lange’s previous moon-phase models with solid-gold lunar discs, the GRAND LANGE 1 MOON PHASE “Lumen” has a disc made of glass. Initially, its surface is treated with a patented coating process. In a second step, a laser is used to cut out 1164 stars and the moon. Thanks to the luminous compound behind the lunar disc, they shimmer with vibrant radiance. The large moon-phase display occupies a prominent position on the main dial. Once properly set, it only needs to be corrected by one day every 122.6 years,” according to A. Lange & Sohne.
The functions include hours, minutes, subsidiary seconds with stop seconds, power reserve indicator, luminous outsize date, and moon phase display. The crown allows winding of the watch and setting the time, with one button for quick outsize date corrections, and a recessed push piece for correcting the moon phase display.
Starting with a solid silver dial, with a black oxidized finish, and combined with a semi-transparent sapphire crystal, luminous Roman numerals, and markers, and luminous hands rhodium-plated gold hands, indicate the time, power reserve, date, and moon phases.
Presented in a 41 mm platinum case, the Grand Lange 1 Moon Phase “Lumen” comes on a black hand-stitched alligator leather strap with a platinum deployant buckle, and is limited to 200 pieces.