Monochrome Watches
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The Arnold & Son Luna Magna Platinum

Arnold & Son’s large 3D moon phase complication now floats in a gleaming platinum case.

| By Rebecca Doulton | 4 min read |
Arnold & Son Luna Magna Platinum

Since the dawn of time, humans have been tracking the phases of the Moon. The brightest and largest object in our night sky, the Moon’s strong gravitational pull is not only responsible for the changing tides but also acts as a stabiliser to keep the Earth from wobbling as its spins on its axis. But the Moon is also an object of incredible beauty and exerts its gravitational pull on our hearts and minds. Watches with moon phase complications are a miniaturised, portable representation of the waxing and waning of our celestial neighbour, bringing a touch of poetry and beauty to the more prosaic passing of time. Arnold & Son has produced several moon phase watches over the past years, but nothing like the impressive Luna Magna unveiled earlier this year during Watches & Wonders with its large 3D rotating Moon in a red gold case. Following the success of this model, Arnold & Son releases a second edition in platinum with a mother-of-pearl dial.


Arnold & Son has produced various moon phase watches over the years, including the 2016 Perpetual Moon and the Double Hemisphere Perpetual Moon. Beautifully crafted with photorealistic representations of the Moon, these models were fitted with a precision display that only deviates by one day every 122 years. However, since the Moon is not flat, Arnold & Son designers decided to capture the three-dimensionality of the Moon with the stunning Luna Magna. Marking the brand’s first 3D Moon, the Moon rotating on the dial of the Luna Magna is, as its name suggests, great (large).

Arnold & Son Luna Magna Platinum

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A large round aperture on the dial at 6 o’clock houses the 12mm sphere representing the Moon. Composed of blue aventurine glass and grey marble, the Luna Magna is one of the largest 3D moons ever incorporated on a wristwatch. The grey area of the Moon is realistically rendered with patches of darker grey areas to suggest craters; the aventurine half of the Moon sparkles like a beautiful night sky. The ever-changing nature of the Moon is well captured with the chiaroscuro effect produced by the contrasting blue aventurine and grey marble.

Astronomical accuracy is guaranteed by the precision moon phase complication developed by Arnold & Son. Taking into account the 29 days, 12 hours, 44 minutes, and 2.8 seconds of a complete lunar cycle, Arnold & Son precision complication ensures that if the watch were kept wound, it would only need a one-day adjustment in 122 years. However, there is a practical way to correct the moon phases directly at the crown.

Gleaming platinum

Compared to the earlier red gold model, the platinum case gives the watch a colder, more majestic aura, closer to our perception of the silvery Moon. The 950 platinum case, measuring 44mm across and 15.90mm thick, is polished throughout. Despite the substantial height of the case – necessary to accommodate the 3D moon phase complication and the two box-sapphire crystals – the case has an elegant profile.

Arnold & Son Luna Magna Platinum

Starry, starry night

A sparkling aventurine dial provides a starry stage for the time and rotating spherical Moon. Apart from the platinum case, the other novelty of this model is the mother-of-pearl dial at noon with classic Roman numerals and openworked blued hands. The beauty of mother-of-pearl is its warm, natural iridescence that also interacts with light. Used as the background of the hour and minute functions, the mother-of-pearl looks almost like white billowing clouds.

Arnold & Son Luna Magna Platinum

Hand-wound calibre

The reverse side of the case offers a generous view of the A&S1021 calibre, a hand-wound movement beating at 21,600vph/3Hz with a robust 90-hour power reserve. What is particularly beautiful is that you can see the other side of the spherical Moon on the caseback (framed by a pink ring), which also explains why there is a domed sapphire crystal over the movement. Just above the sphere is a more accurate indicator of the eight phases of the Moon (New Moon, Waxing Crescent, First Quarter, Waxing Gibbous, Full Moon, Waning Gibbous, Last Quarter and Waning Crescent).

Arnold & Son Luna Magna Platinum

The movement has a diameter of 37.6mm and, including the 3D Moon, the height is 12mm; without the Moon, it measures a slim 4.75mm. Like all A&S movements (which are made by La Joux-Perret, part of the Citizen Group, and sister company of Arnold & Son), the finishing is traditional with Geneva stripes radiating from the centre of the movement, blued, chamfered screws with polished heads and circular graining with a satin finish on the wheels.

Availability & Price

The Arnold & Son Luna Magna Platinum comes with a blue alligator leather strap with a dark magenta lining (to match the frame of the sphere on the movement side) and a platinum pin buckle. Limited to 28 pieces, the price of the Luna Magnum Platinum is CHF 55,900.

Arnold & Son Luna Magna Platinum

For more information, please visit Arnold & Son’s website.

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