For a brand that prides itself on its history and tradition of skeletonisation, it was only a matter of time before Armin Strom presented a watch with a sapphire watch case. The surprise is the fact that the brand chose to do so for its huge 59mm long Dual Time Resonance model. Sapphire crystal cases are notoriously difficult to produce. Diamond-tipped tools are needed to work the material (since only moissanite and diamond are harder the sapphire crystal on the Mohs scale), but even then the friction between the two materials generates heat and can lead to breakages. The few cases that survive the machining process intact subsequently need a few days’ rest to allow the heat to dissipate before any further work can be done on them. Polishing the opaque machined crystal to achieve the full transparency you see on the finished product also takes several days, still with that ever-present risk of breakage…
But all this complicated and time-consuming work is a mere trifle compared with the three years of development that went into the mirrored force resonance calibre found inside. “A lot of work is done by hand and we wanted to have the possibility to show off the decoration from every angle,” says Serge Michel, founder of Armin Strom. Now that every minute detail of this movement is on show, however, there is arguably even more pressure on Claude Greisler, the co-founder of Armin Strom and the man behind the remarkable mirrored force resonance concept. As he explains, “this new sapphire case sets the perfect stage for the detailed work and passion we put into the Dual Time Resonance. The total transparency does not allow for any mistakes and demands a finish on the highest level, which goes in line with our philosophy.”
The view through the sapphire crystal case shows two independent movements (allowing two different time zones to be displayed) coupled by Armin Strom’s patented Resonance Clutch Spring, which is the key component that allows the two movements to beat in resonance. Switzerland’s CSEM (Centre for Electronics and Microtechnics) has officially certified this system as being a true system in resonance. Armin Strom’s own laboratory testing has shown improvements in the order of 15-20% for two COSC-certified movements placed in resonance.
This transparent and scratch-resistant marvel is available as a limited edition of just eight watches, each costing a cool 280,000 Swiss francs.
