$275,000.00
Movement: Manufacture Calibre MB M65.63
Case: 47mm x 15mm 18k white gold teardrop case
Dial: Open movement mainplate serving as the dial surface, one-minute tourbillon at 12 o’clock, Heures Mystérieuses display with hour and minute hands on transparent rotating sapphire discs at 6 o’clock
Bezel: Integrated 18k white gold, concave cross-section from 8 through 12 to 4, transitioning to convex from 4 to 8, polished throughout
Strap: Black leather with alligator finishing, white gold pin buckle
Box/Papers: This example comes complete with the Montblanc piano black presentation box, a loupe, full papers, all booklets and accessories, and the outer shipping box. Everything is present.
The Tourbillon Bi-Cylindrique is the piece that established what the Villeret manufacture, the former home of Minerva, was truly capable of. Introduced in 2011, it holds a distinction no other wristwatch had claimed before it: the world’s first tourbillon fitted with a double cylindrical balance spring, a complication originally developed for 18th-century marine chronometers. The two cylindrical hairsprings are positioned concentrically, one inside the other, each with its own diameter but both engineered to deliver identical torque to the movement. Expanding and contracting in opposite phase, they produce a dramatically flatter effective torque curve and push isochronism beyond what a single flat spiral spring can achieve. The one-minute tourbillon carriage housing all of this is composed of 95 hand-chamfered, beveled, angled, and polished components, with the bridge alone requiring nearly a week of hand-finishing to complete. Time is displayed via the Heures Mystérieuses complication, with hour and minute hands appearing to float on transparent rotating sapphire discs, the peripheral gearing visible through the open dial architecture. The teardrop case tapers toward six o’clock with a cambered profile and a concave-to-convex bezel transition, one of the most structurally demanding case forms in contemporary watchmaking. Eight pieces produced in white gold total.