Monochrome Watches
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Independent Watchmaking

Sarpaneva Lunations and the Latest Iteration, the Harvest Moon

The Northern Moon shines brighter than ever.

| By Xavier Markl | 4 min read |
Sarpaneva Lunations

Stepan Sarpaneva crafts watches like no other. The independent Finnish (that in itself is already unusual) watchmaker has shaped a personal creative universe giving his watches a distinctive Moon face. His intriguing and mysterious representation of our satellite has made his timepieces recognizable at a glance. His latest creation, Lunations, distils the essence of 25 years of watchmaking expertise and creativity. The watch is powered by Sarpaneva’s first in-house calibre, which integrates an ultra-precise moon phase with a lunation period of 9 days, 12 hours, 44 minutes and 2.3 seconds. This means that it needs to be adjusted for a single day of error only once every 14,000 years. But there is more. Let’s take a closer look.

The ‘Moonment’ project started back in 2011. At the time, the Finnish watchmaker had been around for years in the watch industry but thought it was time to come up with something that would be the next generation Sarpaneva watch by creating its own in-house movement. In particular, it would be the opportunity to design something that celebrates his brand’s signature feature, a movement built around the complication – and not the contrary, which is usually the case. To do so, he cooperated with another figure of independent watchmaking, Andreas Strehler, specifically on the calculation of the gearing of the movement.

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Fusion Studio TIFF File

The synodic month, corresponding to the Moon visible in the sky is the measurement used by watchmakers. It has an average length of 29.530587981 days or 29 days 12 hours 44 minutes and 2.80 seconds to reproduce the progression of our satellite – the simplest moon phase watches feature a wheel with 59 teeth (2 x 29.5 days). Such mechanisms provide an approximation of the moon phase that needs to be corrected by one day every two and a half year. The closer the moon phase calculation comes to the average lunation, the more precise it will be. With more sophisticated mechanisms, the gear ratio can increase precision to one day over a period of more than a century, a millennium… and up to 14,000 years in the case of the Sarpaneva Lunations, making this development one of the most precise moon phase watches ever. To date, the record is held by the Sauterelle à Lune Perpétuelle 2M presented by Andreas Strehler in 2015 requiring a correction of one day for approximately 2.060 million years, no less. An identical mechanism can be found on this “Lune Exacte” too.

Fusion Studio TIFF File

But the charm of the Sarpaneva Lunations goes way beyond precision, technical aspects or the ingenuity of its moon phase mechanism. From a design perspective, the moon phase indication takes centre stage. The large moon phase aperture is filled with a cross-section of optical fibre on which the signature Sarpaneva moon face has been laser engraved and hand-finished. At the back of the movement, twin-discs inset with luminescent RC Tritec’s Lumicast® rotate to indicate the visible section of the moon with striking 3-dimensionality. 

The movement is skeletonized to replicate the traditional Sarpaneva style. It reveals its intricacies including the pulsating balance wheel between 2 and 3 o’clock through an opening (the movement is an inverted construction). Light becomes an integral part of the watch design. Not just with the moon but also with the luminescent indexes, the hands and the openwork parts. Turning the watch over, the exhibition caseback reveals the cool twin ‘moons’ in orbit while providing an indication of the age of the moon in days.

The ‘Moonment’ runs at 21,600 vibrations per hour and stores 60 hours of power reserve when fully wound. It is housed in the Sarpaneva signature case, standing out with its unusual shape, short lugs and integrated strap. 42mm in diameter, it is presented in high-grade Outokumpu supra 316L/4435 steel or in pink gold. It is water-resistant to 5 ATM / 50 metres. Last but not least, not only is Sarpaneva Lunations uniquely precise in its display, but it is also uniquely precise (and user-friendly) in the way it is set. All settings are performed via the crown and not via correctors as is the case with most moon phase watches. 

The Sarpaneva Lunations is worn on a leather strap (various colours available) with pin buckle. The watch can be extensively customized to reflect the lunar cycle in both northern and southern hemispheres. It is priced at EUR 33,000.

The new ‘Harvest Moon’ version

The Finnish indie watchmaker now presents a new, cool version of its Lunations. Dubbed ‘Harvest Moon’, it comes with orange moons, an option reserved for 10 watches only. The harvest moon is the name given to the full moon that occurs around the autumn equinox and that tends to look reddish/orange. For the new Sarpaneva watches, the moon appears ‘white’ in daylight and glows orange in the dark. As for the original versions of the Sarpaneva Lunations, the Harvest Moons can be customized. Price starts at EUR 35.000.

Sarpaneva Lunations Harvest Moon

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