Arnold & Son recently debuted their HM Perpetual Moon wristwatch in a steel case with a lacquered blue guilloché dial.

According to the company, it’s 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.”

It also has one of the largest moon phase apertures, taking up most of the top half of the dial. Underneath the dial, is a blue guilloché moon disc with a golden moon and stars that is 29 mm in diameter. The moon alone is 11.2 mm. The intricate three-dimensional moon was first hand-engraved and then duplicated for the series.

In addition to the dial side moon phase, the backside of the movement also has a moon phase indication with 8 phases of the moon. “From the technical side, in addition to the HM Perpetual Moon being so precise, it is also an intriguing complication in that it is not simply a module added to the movement, but 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 case back, features a graduated dial and a pointer hand that allows for a more exact setting.”

The HM Perpetual Moon case is 42 mm in diameter and has a stepped design that tapers from top to bottom. The front has a cambered sapphire crystal and on the back is a sapphire window, offering a view of the beautifully detailed movement. Water-resistant is rated to 30 meters. Each is finished with a hand-stitched alligator strap.Inside, is an exclusive Arnold & Son mechanical hand-wound movement (caliber A&S1512). It features a double barrel good for a maximum of 90-hours power reserve. The nickel-silver components movement has been rhodium plated. The bridges have a sunray Geneva striped decoration (Côtes de Genève rayonnante), the mainplate has a perlage finish, screws are blued, and the wheels have a snailed finish. Furthermore, all the bridges have manually chamfered bridges with polished edges. (Ref. 1GLAS.U02A.C122S)

The retail price is $17,200.

Posted by:Jason Pitsch

Jason is the founder of Professional Watches and specializes in writing, product photography, and digital marketing.