The New Armin Strom Gravity Equal Force Ultimate Sapphire Blue

When Serge Michel and Claude Greisler acquired Armin Strom, they took the bull by the horns. Without abandoning Mr Strom’s famous hand-skeletonised movements, the pair developed a full-scale vertical manufacture and successfully addressed the phenomenon of Mirrored Force Resonance in a wristwatch format. Another horological success story was the brand’s Gravity Equal Force watch of 2019, the world’s first automatic watch equipped with a stop-work declutch mechanism, ensuring consistent power to the balance throughout its 72-hour power reserve. A member of the System 78 collection with more accessible, entry-point prices, the Gravity Equal Force’s best-selling status means that it is constantly revisited in new colour combinations and materials. With summer in full swing, Armin Strom releases a glacial blue iteration to recall the refreshing waters of Switzerland’s lakes and alpine light.

Explained in great detail here, master watchmaker Claude Greisler’s stop-work declutch system addressed a problem shared by all watches. The force that a mainspring can deliver as it unwinds can never be consistent because the force provided will be higher when fully wound and wanes towards the end of its power reserve. This fluctuation affects the rate of the movement. To avoid the extremes of high and low torque periods, a stop-work mechanism combined with a Geneva cross inside the barrel stops the mainspring from fully unwinding. It leverages the stage of the unwinding process when it can deliver consistent power. In true Armin Strom style, Greisler’s technical breakthrough was not hidden on the caseback but revealed on the dial.

The aesthetics of the watch are a fusion of old and new. The three straight parallel or finger bridges on the right evoke the architecture of pocket watches. At the same time, the openworked dial with its off-centred hour and minute disc adds a contemporary touch. Appearing in many colours since 2019, including MONOCHROME’s very own Montre de Souscription, the cooler, glacial-toned colour of the Ultimate Sapphire Blue is an antidote to the hot summer days.

The richly textured mainplate is decorated with a barley grain hand-guilloché pattern performed by artisans in Kari Voutilainen’s dial atelier (Comblémine SA), followed by a 3D PVD process to produce the light blue colour. Although the time indications are off-centred, the dial has a pleasing symmetry with the three openworked finger bridges on the right securing the linear components. The bridge at 1 o’clock secures the round aperture of the micro-rotor, forming a visual counterweight to the bridge over the equal-force barrel at 5 o’clock.

To provide a full view of the movement, the hour and minute disc is made of light grey sapphire crystal with its hallmark intersecting small seconds sub-dial. The faceted and polished hour and minute hands are filled with Super-LumiNova. Every component of the ASB19 automatic movement is hand-finished in the brand’s manufacture in Biel, including the bevelled and polished bridges and the black-polished screws. Assembled twice, the movement also features traditional decorations, such as perlage and Geneva stripes.

Thanks to the incorporation of a micro-rotor, the case has a reasonably slim profile of 12.65mm coupled with a diameter of 41mm. Alternating brushed and polished finishes highlight the case’s architectural lines with sapphire crystals showcasing the movement on both sides.

The Gravity Equal Force Ultimate Sapphire Blue is paired with a blue nubuck leather strap with ice blue stitching. It is a limited annual series of 25 pieces, retailing for CHF 27,500. More information at arminstrom.com.