Arnold & Son continues to explore the theme of moon phases by launching a new interpretation named Perpetual Moon 41.5 Platinum Celestial Blue.
In a platinum case measuring 41.5 mm in diameter and 11.30 mm thick, Perpetual Moon 41.5 Platinum “celestial blue” presents the largest of all moons.
This edition showcases the latest characteristics of the Perpetual Moon collection, substantially redesigned to achieve greater refinement and subtlety. The lugs have been simplified and refined. Instead of their original cross shape, they now present a tauter form of plunging bars with bevelled ends. They form a single piece with the case middle, in terms of both their construction and appearance.
After remaining at 42 mm for a long time, the case has been slightly reduced to 41.5 mm without altering the dial opening, giving a slimmer bezel instead. As a result, the eye is drawn in towards the dial, its finishes, its immense moon and its dominant pale-blue shade.
The dial is adorned with the “Stellar Rays” finish. Its aesthetic is obtained through skilfully irregular engraving. Various depths and widths of rays are successively combined to create a specific rhythm. Their sequence produces a fluctuating play of light, which is accentuated by the depth created by several layers of transparent lacquer.
The large white mother-of-pearl moon is realistically rendered with hand-painted shadows and coated with Super-LumiNova. It is placed on a grained sky featuring a midnight-blue PVD treatment. Following the tradition of the Perpetual Moon collection, it is surrounded by the Big Dipper and Cassiopeia constellations, which are also hand-painted and coated with luminescent material.
The constellations have been chosen as a reference to John Arnold’s history as a maker of naval chronometers. The Big Dipper and Cassiopeia have been used as points of reference since time immemorial. Midway between these easily identifiable constellations is the North Star.
Its position inevitably defines the North and its angular altitude, or position in the North-South plane, and allows the distance to the equator, i.e. the latitude, to be estimated. Before instruments for measuring longitude were invented, it was the most reliable way to determine the position of a boat in the middle of the ocean.
On the case back, a secondary indicator allows the moon phase to be adjusted quickly and precisely. Powering this moonphase watch is the exceptionally precise hand-wound calibre reference A&S1512.
The duration of a complete lunar cycle is 29 days, 12 hours, 44 minutes and 2.8 seconds. It would take 122 years for this movement, if regularly wound, to accumulate a day’s difference between its display and celestial reality.
Like all Arnold & Son movements, the A&S1512 calibre has been entirely developed, manufactured, decorated, assembled, adjusted and cased at the Manufacture in La Chaux-de-Fonds. The calibre features two barrels and an oscillating frequency of 3 Hz, providing a power reserve of 90 hours.
The Arnold & Son Perpetual Moon 41.5 Platinum Celestial Blue watch comes with a navy-blue alligator-leather strap.
Technical details
Model: Arnold & Son Perpetual Moon 41.5 Platinum “celestial blue”
Reference 1GLBX.U01A.C200X
Functions
Hours, minutes, astronomical moon phases, second moon-phase indicator on the back
Movement
Calibre A&S1512, mechanical with manual winding
Jewels: 27
Diameter: 34 mm
Thickness: 5.35 mm
Power reserve: 90 hours
Frequency: 3 Hz/21,600 vph
Finishes
Main plate: Rhodium-plated, radiating Côtes de Genève stripes
Bridges: Polished and chamfered
Wheels: Circular satin-finished
Screws: Blued and chamfered, polished heads
Second moon-phase indicator: Rhodium-plated and circular-grained
Dial
“Stellar Rays” décor, with celestial-blue PVD treatment
Sky: grained, with midnight-blue PVD treatment
Constellations: hand-painted, enhanced with Super-LumiNova
Moons: mother-of-pearl discs enhanced with Super-LumiNova, hand-painted details
Case
Platinum (Pt 950)
Diameter: 41.5 mm
Thickness: 11.30 mm
Crystal: Domed sapphire with an anti-reflective coating on both sides
Case back: Sapphire crystal with an anti-reflective coating
Water resistance: 3 bar (30 metres/100 feet)
Strap
Blue alligator leather, hand-stitched
Clasp: Pin buckle, 18-carat white gold
Edition
Limited edition of 38 timepieces
Swiss retail price
CHF 46,600 incl. tax (subject to change)