HM Perpetual Moon Aventurine in hand

HM Perpetual Moon Aventurine

March 19, 2019

Demonstrating its rich British history and quality Swiss craftsmanship, Arnold & Son unveils a new version of the HM Perpetual Moon with a blue aventurine-stone dial.

The HM Perpetual Moon is a testament to Arnold & Son’s tradition of watches with astronomical indications. Part of the Royal Collection, this timepiece demonstrates the brand’s prowess in traditional watchmaking and classical decorative arts.

The sophisticated HM Perpetual Moon Aventurine is, indeed, a superb example of Arnold & Son’s technical and artistic excellence. From the inside out, this new timepiece with rich-blue guilloché moon disc and engraved moon surprises and delights. It houses the exclusive Arnold & Son mechanical hand-wound movement, caliber A&S1512. This caliber was developed especially for our moon phase watches with the objective of offering a uniquely precise, big and three-dimensional moon phase. The caliber is also equipped with a double barrel to yield 90 hours of power reserve.

The HM Perpetual Moon Aventurine offers one of the most accurate moon phases on the market, with only one day’s deviation every 122 years at which point a single push on the corrector will keep it in sync for another 122 years.

The exceptional perpetual moon phase indication of this watch is a marvel in many ways. From the aesthetic side, the 29mm moon phase disc, which runs from 10 to 2 o’clock on the dial, reveals one of the largest moons on the market with a diameter of 11.2mm for the moon alone. Additionally, this large moon is one of the most visually stunning recreations of the moon because it is a three-dimensional sculptured moon that was first hand-engraved and then duplicated in a rose gold plate for the series. The sculptured moon is then inserted into the guilloché disc.

From the technical side, in addition to the HM Perpetual Moon Aventurine being so precise, it is also an intriguing complication in that it is not simply a module added to the movement, but, in fact, is fully integrated into the caliber. The watch also has a unique easy-to-set feature thanks to the ingenious addition of a second moon indication installed at the back of the movement. This second moon display, visible via a transparent caseback, features a graduated dial and a pointer hand that allows a more exact setting.

The multiple technological advancements in the caliber make this timepiece truly outstanding. To further underscore that, the entire rhodium treated nickel-silver movement features hand finishing indicative of the finest haute horlogerie timepieces, including manually chamfered bridges with polished edges, Côtes de Genève rayonnantes and fine circular graining, circular-grained wheels, and blued screws with polished and chamfered edges. The timepiece naturally features an anti-reflective sapphire crystal and caseback to view the meticulous details.

The HM Perpetual Moon Aventurine measures 42mm in diameter in its classically elegant rose gold case. Viewed from the side, the housing is stepped and tapers from top to bottom, the widest section accommodating the extra-large glass with the lower part narrowing to fit snugly on the wrist. Each is finished with an exquisite hand-stitched alligator strap. In all, the HM Perpetual Moon Aventurine is a beguiling work of technical mastery and fine art.