Zenith’s G.F.J. Calibre 135 Jasper Bloodstone brings the collection into a warmer register, pairing an 18-carat yellow gold case with a natural stone dial that gives every piece its own character.
Introduced at Watches & Wonders 2026 alongside a tantalum version, this model follows the platinum G.F.J. that won the 2025 GPHG Chronometry Prize and builds on the same compact, chronometer-led formula.
Bloodstone gives the G.F.J. a less formal face
The dial is the immediate draw: a dark green jasper bloodstone centre with mottled mineral texture and small red iron-oxide flecks running through the surface.
Natural stone changes the personality of a watch because it refuses perfect uniformity, and that works especially well here against the structured geometry of the G.F.J. dial layout.
At 6 o’clock, the small seconds sits on a green mother-of-pearl disc, while the hour track carries Zenith’s brick-pattern guilloché motif, a detail tied to the architecture of the brand’s historic Le Locle manufacture.
The 18-carat yellow gold hands and indexes keep the dial legible without flattening its depth, and they make the green tones feel richer rather than louder.
A 39.15mm yellow-gold case keeps the balance
The case measures 39.15mm across and 10.5mm thick, which is a sweet spot for a dress-leaning watch with a substantial movement story behind it.
Yellow gold can easily dominate a design, but the G.F.J. case tempers the metal with brushed and polished surfaces, stepped lugs and a partially recessed crown.
The bezel is not a simple polished ring; its angled surfaces catch light in smaller flashes, giving the watch presence without making it feel oversized.
A sapphire display back opens the view to the Calibre 135, which remains the reason this watch carries more weight than a conventional precious-metal dress piece.
The revived Calibre 135 still does the serious work
Inside is Zenith’s hand-wound Calibre 135, running at 2.5Hz with a Breguet overcoil, stop-seconds function and COSC chronometer certification.
The movement offers a 72-hour power reserve, a major modern improvement over the historic architecture’s earlier 40-hour reserve, and the specification suits a watch intended to be worn rather than merely admired.
For the Jasper Bloodstone model, Zenith gives the movement a darker and more contemporary finish, with perlage on the mainplate, broad Côtes de Genève across the bridges, hand-chamfering and a ruthenium-toned treatment with gold-coloured engraving.
The crown wheel and ratchet wheel are sunray-brushed, a small detail that matters when the entire concept depends on visible mechanical refinement.
Strap options and collector appeal
Zenith supplies the watch with three straps: beige nubuck leather, green alligator leather and black calfskin leather, each changing the tone of the piece quite noticeably.
An 18-carat yellow gold bracelet with a double folding clasp is also offered as an additional option, pushing the watch into a more assertive and jewellery-adjacent space.
The Jasper Bloodstone will appeal to collectors who like the technical seriousness of the Calibre 135 but want a less austere expression than platinum or tantalum.
It is not the quietest G.F.J., and that is exactly its point: the watch keeps the collection’s chronometric credibility intact while adding warmth, texture and a welcome sense of individuality.
