End Of An Era: A Farewell To Greubel Forsey The S² Calibre

Greubel Forsey unveils the final two editions of the Balancier Convexe S². One in black ceramic and 5N red gold, the other in white ceramic marking the conclusion of a calibre developed and built over the past five years. Each edition is limited to only 11 timepieces, making them the most exclusive executions of the series. Housed in the signature Convexe case measuring 41.5mm across the caseband and built around the hand-wound 30° inclined balance wheel sys­tem, these editions represent the definitive ex­pression of the Balancier Convexe S² movement. With their release, the calibre enters its final phase: production will cease permanently in 2026, closing this chapter of Greubel Forsey’s mechanical development.

From its origin, the Balancier Convexe S² was de­signed as a fully integrated object in which case geometry and movement structure evolve together. The Convexe architecture follows the natural cur­vature of the wrist, allowing the three-dimensional movement to remain balanced, legible and com­fortable in daily wear. Rather than enclosing the calibre, the case extends its architecture outward, reinforcing the dialogue between exterior form and mechanical construction.

At the heart of the movement lies Greubel Forsey’s 30° inclined balance wheel system, positioned as the visual and chronometric centre of the composition. The movement is built around openness and perspective, with multi-level bridges and suspended structures designed to reveal rather than conceal mechanical function. Composed of 301 components, with an escape­ment platform of 68 parts, the calibre combines structural lightness with technical density. Two fast-rotating coaxial barrels provide a 72-hour chronometric power reserve, while the in-house variable-inertia balance with six gold mean-time screws operates at 21’600 vibrations per hour.

The finishing philosophy remains fundamental to the identity of the timepiece. Titanium bridges and main plates are frosted and hand-finished with polished bevels, countersinks and carefully executed transitions between surfaces. Every component is treated with the same level of atten­tion, including areas that remain largely unseen, reflecting a consistent approach to execution where integrity of construction prevails over visi­bility. The two final editions express contrasting visual identities while sharing the same mechanical foundation.

The black ceramic and 5N red gold edition em­phasises contrast and depth. Black-treated movement components and the ceramic case frame the architecture, while the red gold bezel and caseback introduce warmth and visual weight. The interplay between matte and pol­ished surfaces amplifies the three-dimensional character of the movement and reinforces the sculptural nature of the Convexe case.

The white ceramic edition explores the opposite approach. The monochromatic light-toned case accentuates openness and precision, allowing the movement to emerge through light and shad­ow. The result is a more technical and graphic ex­pression, where structure becomes the primary visual language. The white ceramic construction highlights the purity of the Convexe geometry while preserving the same mechanical depth and legibility.

Both editions retain the essential functional layout of the Balancier Convexe S²: hours and minutes displayed on a suspended arch bridge, small seconds, and a sector power-reserve in­dication. The curved sapphire crystals, three-dimensional bezel geometry and profiled lugs reinforce the continuity between movement architecture and exterior form, maintaining the balance between presence and wearability that defines the Convexe approach.

These two editions complete a five-year explora­tion of the Balancier Convexe S² calibre through different material and aesthetic interpretations. Their release marks not an evolution, but a con­clusion. In 2026, production of the movement will end permanently.

The year 2026 also marks the beginning of a gradual transition toward an almost entirely new collection. As Greubel Forsey closes the chapter on calibres that have shaped the past years of technical and creative development, each will be retired deliberately not silently with a final expression that celebrates its contribution to the Atelier’s continuous evolution.

Limited to only 11 timepieces per edition, the black ceramic / 5N red gold and white ceramic executions stand as the final and most exclusive expressions of the Balancier Convexe S² the closing statement of a calibre defined by archi­tecture, chronometric intent and mechanical coherence.