Introducing the Senans Grande Lune, YEMA's first moonphase timepiece and the inaugural model of the new Senans collection.
A sculpted, luminous Moon takes a prominent place on an intricately textured dial, transforming a traditional complication into the defining feature of the watch.
Powered by the new CMM.22 Manufacture micro-rotor movement, the Grande Lune combines an ambitious lunar complication with the refined proportions of a stainless steel case measuring just 8.70 mm thick.
Limited to 200 pieces per dial colour.
A New Perspective on the Moon
Traditionally confined to a small aperture, the moonphase complication finds a more expressive setting in the Senans Grande Lune.
Positioned asymmetrically at 7 o’clock, the prominent lunar display immediately draws the eye and defines the character of the dial. The surrounding guilloché textures, hour markers and open space counterbalance its unconventional placement, giving the dial a distinctive yet carefully balanced design. Unlike conventional flat moonphase discs, the Senans Grande Lune features a three- dimensional Moon, giving the lunar display a sculptural presence.
A rotating mechanical bilobe gradually reveals and conceals the Moon, recreating the succession of lunar phases. A familiar astronomical cycle unfolds on your wrist, inviting a closer look each day.
Patterns Inspired by Nature
The central dial features a circular barleycorn guilloché, with repeating grain-shaped motifs arranged in concentric circles. The composition draws inspiration from the Fibonacci spiral and the patterns found in nature.
Its flowing texture creates an impression of rotation and depth, guiding the eye towards the Moon at 7 o’clock. As light moves across the surface, changing reflections reveal the fine relief and geometry of the pattern. Surrounding the central guilloché, circular-brushed surfaces provide a smoother contrast to the finely textured centre.
The interplay of geometry, texture and light gives the Senans Grande Lune its distinctive visual character, creating a sense of movement even when the watch is still.
From Daylight to Moonlight
Crafted from a solid block of Grade X Super-LumiNova using Globolight technology, the Moon forms a sculptural, three-dimensional luminous element.
Its subtly domed surface features finely detailed lunar markings, reproducing the characteristic craters and irregular textures of the Moon’s surface. By day, these details give the display realism and depth. As darkness falls, the Moon reveals a different character, emitting a soft, warm glow reminiscent of natural moonlight.
Concentric Super-LumiNova rings frame the central guilloché like luminous halos, extending the Moon’s glow across the dial. Luminous hands and applied hour markers complete the display, keeping the time legible while allowing the Moon to remain the focal point, day or night.
Every Detail in Harmony
Polished applied hour markers alternate between long and short forms, evoking rays of light spreading from the centre. The spaces between them allow the Moon and the Manufacture Française inscription to sit naturally within the composition. Slender, polished hour and minute hands bring lightness to the dial, their clean profiles leaving its richly textured surface open to view.
The off-centre Manufacture Française inscription completes the composition, balancing the Moon at 7 o’clock while keeping the lettering clear against the textured dial.
Classical Stepped Case Design
The Senans Grande Lune features a classical stepped case, distinguished by its layered construction, where the bezel rises in successive levels above the case middle.
Measuring 38.5 mm in diameter, just 8.70 mm thick and 46.4 mm from lug to lug, the 316L stainless steel case combines classical proportions with a comfortable wrist presence. The mirror-polished bezel and upper surfaces contrast with vertically brushed sides, emphasising the stepped architecture, while gently curved lugs follow the contours of the wrist. Its slim profile allows the watch to slip easily beneath a shirt cuff. A double-domed sapphire crystal with anti-reflective coating completes the case, its gentle curvature recalling traditional watch crystals while providing a clear view of the intricate dial and sculpted lunar display.
The Engineering Behind the Big Moonphase
Integrating a large moonphase complication into an ultra-thin automatic movement presented a significant mechanical challenge. The larger lunar mechanism introduced additional mass and inertia compared with conventional, smaller moonphase displays. This required careful refinement of component dimensions, gearing and the transmission of power through the mechanism.
YEMA’s movement engineers developed the mechanism through successive stages of design and prototyping, incorporating a dedicated component measuring just 0.83 mm thick. A quick-adjustment system allows the wearer to set the lunar display conveniently, adding a further engineering challenge within the limited space available. Building on YEMA’s 3.7 mm CMM.20 micro-rotor architecture, the team integrated the moonphase complication while adding less than 1 mm to the base movement’s thickness. The resulting CMM.22 Manufacture caliber measures less than 4.7 mm thick, allowing the Senans Grande Lune to combine its prominent lunar display with a slender 8.70 mm case profile.
Senans: Inspired by French Architectural Heritage
The Grande Lune inaugurates a new family of YEMA timepieces inspired by the Royal Saltworks of Arc-et-Senans, an 18th-century architectural landmark in eastern France, not far from YEMA's workshops in Morteau. Designed by the architect Claude-Nicolas Ledoux during the Age of Enlightenment and recognised as a UNESCO World Heritage Site, the Royal Saltworks is celebrated for its distinctive semicircular layout.
Built between 1775 and 1779, the Royal Saltworks represents an ambitious vision of architecture in which classical proportions, geometric precision and industrial purpose come together. Its buildings are arranged around a central space, creating a monumental composition defined by symmetry and sweeping curves.
Taking its name from Arc-et-Senans, the new Senans collection draws inspiration from this architectural heritage. The sweeping semicircular geometry of the Royal Saltworks finds an echo in the Grande Lune's lunar aperture, creating a visual connection between the historic monument and the watch's defining complication.
The CMM.22 Revealed in Anthracite
Visible through the sapphire exhibition caseback, the CMM.22 Manufacture caliber is derived from YEMA’s CMM.20 micro-rotor architecture, adapted for the moonphase complication and finished in deep anthracite.
A rich charcoal grey with subtle metallic undertones, anthracite offers a distinctive alternative to traditional silver-toned movement finishes. Its darker surfaces bring definition to the movement’s architecture, creating a striking contrast with the polished screw heads, jewel bearings and brushed micro-rotor.
This finish is achieved through an Anthradec electroplated surface treatment. Applied in an exceptionally thin layer, the coating combines high surface hardness with good chemical stability, preserving the fine detail of the underlying surfaces. Against this dark background, metallic components catch the light and the micro-rotor turns with the movement of the watch. The view through the caseback reveals another side of the timepiece, pairing its classical exterior with a distinctly contemporary movement.
