Yema Moves Into Dress Watches With the Senans Grand Lune CMM.22

Yema is best known for tough French tool watches, from the Superman diver to the Flygraf chronograph.

The Senans Grand Lune CMM.22 takes the brand somewhere quieter and more formal, with a slim round case and a moon phase display that’s unusually architectural.

It’s also a useful sign of where Yema’s modern manufacturing ambitions are heading, as the brand continues building around its proprietary micro-rotor movements.

At a glance

• Yema has introduced the Senans Grand Lune CMM.22, a new dress watch collection led by the brand’s first moon phase watch.
• The watch uses a large 3D Super-LumiNova moon and a mechanical bilobe to show the lunar phases inside a slim automatic movement.
• Each of the three dial colours is limited to 200 pieces, priced at EUR 2,470 on leather or EUR 2,570 on mesh bracelet.

From French tool watches to a dressier language

Founded in 1948 by Henry-Louis Belmont in Morteau, Yema made its name with purpose-built watches rather than formal pieces.

The 1963 Superman became one of its defining instruments for professional divers, while the Flygraf chronograph spoke to aviation.

Under Ambre France since 2009, the brand has been pushing back toward French mechanical watchmaking through its Calibre Manufacture Morteau programme.

The ultra-slim CMM.20 micro-rotor calibre arrived in 2022 inside the Wristmaster, then spread into other families including the Superman, Navygraf and the dressier Granvelle collection.

The Senans Grand Lune builds on that platform, but it doesn’t feel like a tool watch dressed up for dinner.

A round case with a Senans reference

The Senans Grand Lune steps away from the cushion-shaped Granvelle and uses a more classical round case with a mirror-polished stepped bezel.

The reference point is vintage Calatrava-style dress watch design from the 1940s and 1950s, though the proportions are modern.

The case measures 38.5mm across, 8.7mm thick excluding the double-domed sapphire crystal, and 46.4mm from lug to lug.

Brushed case flanks contrast with the polished bezel, while the lugs curve gently toward the wrist.

The collection takes its name from the Royal Saltworks of Arc-et-Senans, an 18th-century architectural landmark near Morteau known for its semicircular geometry.

That architectural cue appears most clearly in the large asymmetrical moon phase opening at 7 o’clock.

The luminous moon is the centre of the watch

The moon phase display is the most distinctive part of the Senans Grand Lune.

Instead of using a conventional printed moon disc, Yema places a stationary moon crafted from a solid block of Super-LumiNova inside the aperture.

The moon is subtly domed and carries realistic lunar markings, giving the complication depth as well as a pronounced glow in the dark.

To show the lunar phases, Yema uses an ultra-thin rotating mechanical bilobe that passes over the luminous moon like a shadow.

The moon display is framed by a stamped barleycorn guilloché-like pattern, which gives the dial a traditional texture around a very contemporary complication.

Super-LumiNova also appears on the hour markers, hands and the ring framing the central guilloché decoration.

The circular-brushed chapter ring uses alternating long and short baton indices, with a raised minutes track around the outside.

Yema offers the Senans Grand Lune in three dial colours, including black, blue and gold.

The CMM.22 micro-rotor calibre

The movement is based on Yema’s CMM.20 micro-rotor calibre, developed with French watchmaker and movement designer Olivier Mory.

For the Senans Grand Lune, Yema and Mory integrated the moon phase into an ultra-thin automatic architecture while accounting for the size and mass of the 3D luminous moon.

The complication adds 1mm to the CMM.20 architecture, bringing the CMM.22 movement height to 4.7mm.

It still beats at 4Hz and delivers a 70-hour power reserve.

The movement is finished in contemporary charcoal grey electroplating, with polished screw heads and purple jewel bearings adding contrast.

Details & Specifications

The Senans Grand Lune is most likely to appeal to collectors who know Yema for its tool-watch history but want to see what the brand can do with a slimmer, more decorative mechanical idea.

It’s a dress watch with a clear French identity, and its glowing moon gives the collection a technical and visual signature beyond nostalgia.