CONCIERGE PRICE: $53,200

The cold glow of a starry night. The diaphanous presence of a large mother-of-pearl moon. The pale reflections of platinum. Perpetual Moon 41.5 Platinum “celestial blue” extends the palette of the collection’s variations, the largest astronomical moon ever. With its dial embossed with the Maison’s “Stellar Rays” motif, its moon disc set against a grained sky, and its navy blue alligator strap, everything about this timepiece evokes the sparkle of night.
Arnold & Son continues to explore the theme of moon phases with an ever-renewed sense of detail and ornamentation. After revisiting the design of Perpetual Moon, this celestial blue version is added to the collection. In the background, the moon-phase complication is brought to the highest graphic level. In a platinum case measuring 41.5 mm in diameter and 11.30 mm thick, Perpetual Moon 41.5 Platinum “celestial blue” reveals the largest of all moons.
Finesses
This edition presents the latest features of the Perpetual Moon collection, extensively modified for purity and subtlety. The lugs have been simplified and refined. From their original stock shape, they have taken on the tauter form of plunging bars with bevelled ends. Their construction and appearance are one with the case. The case, long stopped at 42 mm, has been reduced to 41.5 mm. This slight reduction has been achieved without affecting the dial opening, thus reducing the presence of the bezel. The result is a more focused gaze on the dial, its finishes, its huge moon and its dominant pale blue.
Lights
The dial features the “Stellar Rays” finish. Its aesthetics are achieved through skilfully irregular engraving. Several depths and widths of rays cohabit and follow one another, creating a rhythm of their own. Their interlinking produces a fluctuating play of light, accentuated by the depth created by several layers of transparent lacquer.
Realistically treated with hand-painted shadows, the large white mother-of-pearl moon is added with Super-LumiNova. It is set against a grained sky, treated with midnight-blue PVD. In keeping with the tradition of the Perpetual Moon collection, it is surrounded by the Great Bear and Cassiopeia constellations, also hand-painted and enhanced with luminescent material. The choice of these stellar configurations harks back to John Arnold’s history as a marine timekeeper. The Big Dipper and Cassiopeia have always served as landmarks. Halfway between these easily identifiable groups lies the North Star. Its position inevitably defines North, and its angular altitude, or position in the North/South plane, enables us to estimate the distance to the equator, or latitude. Before the invention of instruments for determining longitude, this was the most reliable measure of a ship’s position in the middle of the oceans.
Precision
On the back, a secondary moon-phase indicator enables fast, precise setting of the moon’s age. The hand-wound caliber that powers it, reference A&S1512, is capable of tracking the evolution of its quarters with exceptional precision. A complete lunar cycle lasts 29 days, 12 hours, 44 minutes and 2.8 seconds. Arnold & Son succeeded in approximating it in such a way that it would be 122 years before this movement, so constantly wound, accumulated a day’s difference between its display and celestial reality.
Like all Arnold & Son movements, the A&S1512 caliber was entirely developed, manufactured, decorated, assembled, adjusted and cased at the La Chaux-de-Fonds factory. The caliber features two barrels and an oscillation frequency of 3 Hz, providing a power reserve of 90 hours.

DEETS

SPECIFICATIONS
General
Perpetual Moon 41.5 Platinum “celestial blue
Functions hours, minutes, astronomical moon phases, second moon phase indicator on back
Movement
Calibre A&S1512, hand-wound mechanical
Stones 27
Diameter 34 mm
Height 5.35 mm
Power reserve 90 hours
Frequency 3 Hz / 21,600 vib/h
Finishes plate: rhodium-plated, Côtes de Genève radiating
bridges: polished and chamfered
wheels: circular satin-finish
screws: blued and chamfered, heads polished
second moon-phase indicator: rhodium-plated and circular grained
Stellar Rays” dial, PVD-treated in celestial blue
Sky moon phases: grained, PVD-treated midnight blue
constellations: hand-painted, added with Super-LumiNova
moons: mother-of-pearl discs added with Super-LumiNova, hand-painted details
Case
Platinum material (Pt 950)
Diameter 41.5 mm
Thickness 11.30 mm
Domed sapphire crystal, double-sided anti-reflective coating
Back sapphire crystal, anti-reflective treatment
Water-resistance 3 bars (30 meters/100 feet)
Strap
Blue alligator leather, hand-sewn
Buckle, 18-carat white gold
Reference 1GLBX.U01A.C200X
Limited edition 38 pieces