25 September

The day in brief

Grönefeld has unveiled the 1941 Quadrivium, an entirely new watch that gathers four of the solutions that have defined the brothers' work into a single calibre: a 7.5-second remontoire, a flying tourbillon, central jumping seconds and a power-reserve indicator. Vacheron Constantin marked 30 years of the Overseas with an ultra-thin perpetual calendar in white gold, limited to 200 pieces. And Breguet has replaced the wave motif on the Marine dials with the hand-guilloché “Quai de l'Horloge” pattern, alongside deeper changes to the design of both references.

Grönefeld gathers four complications in a calibre built from scratch

1941 Quadrivium, 40 mm tantalum case, with the flying tourbillon at 6 o'clock and the remontoire governor on show at 9. © Grönefeld

After years of requests to reissue the One Hertz, the Parallax Tourbillon or the 1941 Remontoire, Bart and Tim Grönefeld chose another route: to bring the ideas behind those watches together in a new movement. The name comes from the medieval quadrivium — arithmetic, geometry, music and astronomy — the four disciplines understood as a single body of knowledge.

The centrepiece is the 7.5-second remontoire. A remontoire is an intermediate spring, placed between barrel and escapement, that is rewound at fixed intervals — here every 7.5 seconds. The escapement therefore stops receiving the barrel's declining torque and always receives the same force, which stabilises balance amplitude across the power reserve. This is constant force in the proper sense, not an error correction.

The governor that controls the rewind sits exposed at 9 o'clock and turns every 7.5 seconds. The remontoire also drives the central jumping seconds: instead of sweeping, the hand advances one second at a time, which demands a stable energy source independent of the going train. At 6 o'clock is the one-minute flying tourbillon, raised slightly above the dial, with a hand-finished three-arm steel cage.

The hand-wound G-09 calibre has 473 components and 49 jewels, and uses two concentric barrels connected in series, giving 50 hours of power reserve. Barrels in series mainly extend running time and keep the movement working in a flatter part of the torque curve, which pairs well with what the remontoire is there to do.

The 1941 case measures 40 mm across and 11.3 mm high. The Premiere Edition is in tantalum, a dense metal that is hard to machine and finish, limited to 28 pieces and announced at 280,000 euros excluding taxes; a further run of 28 pieces in platinum follows at 310,000 euros. Grönefeld says it has temporarily stopped taking orders because of demand.

Vacheron Constantin marks 30 years of the Overseas

Overseas Perpetual Calendar Ultra-Thin (ref. 4300V/220G-H119), 41.5 mm white gold case, 8.1 mm thick, with a lacquered azure dial. © Vacheron Constantin

The Overseas was born in 1996, heir to the 222 of 1977. Vacheron Constantin marks three decades with a 200-piece run of the Overseas Perpetual Calendar Ultra-Thin in white gold, carrying a lighter, less saturated azure than the collection's usual blue.

The case is 41.5 mm across and just 8.1 mm thick, which is little for a self-winding perpetual calendar: the rotor and the calendar discs both add height. The credit goes to the calibre 1120 QP/1, 4.05 mm thick, with 276 components and 36 jewels, running at 19,800 vph (2.75 Hz) for around 40 hours of power reserve. That low frequency is characteristic of the 1120 family, descended from the JLC 920: it costs some short-term stability and buys height.

The movement carries the Hallmark of Geneva, with Côtes de Genève, hand-finished bevels and a 22-karat gold rotor engraved with a compass rose. The calendar needs no correction until 2100. Worth noting: this reference uses a push-pull crown and is rated to 50 metres, against the 150 metres of screw-down Overseas models. It comes with a white gold bracelet and two rubber straps, at an announced CHF 120,000 including taxes (about US$132,000).

Breguet swaps waves for the “Quai de l'Horloge” guilloché

Marine 5517 in white gold, with a hand-guilloché gold dial and applied Breguet numerals on a raised ring. © Breguet

Breguet has reworked the three-hand Marine 5517 and the Marine Chronographe 5527 in white gold, rose gold and titanium. The dials are still solid gold, hand-guilloché, but the wave motif has given way to the “Quai de l'Horloge” pattern, created for the house's 250th anniversary and drawn from the contours of the Île de la Cité and Île Saint-Louis, by the Paris address where Abraham-Louis Breguet made his marine chronometers.

The deeper change is in the numerals: the Roman ones are gone, replaced by Breguet Arabic numerals drawn from marine chronometer No. 104 and applied on a raised ring that lifts them off the guilloché ground. The date has moved from 3 to 6 o'clock, balancing the dial, and the seconds hand carries a tip inspired by the “Bravo” maritime flag.

The 5517 keeps its 40 mm by 11.5 mm case, screw-down crown and 100 metres of water resistance, with the automatic calibre 777A: 4.3 mm thick, 235 components, 4 Hz, 55 hours of power reserve, a silicon balance spring and a gold rotor shaped like a ship's rudder. The 5527, at 42.3 mm by 13.9 mm, uses the 582QA flyback chronograph calibre with 48 hours of reserve, a silicon balance spring and a silicon inverted lever; it drops the chronograph hour counter and now runs two registers.

All models join the permanent collection. For the 5517, announced prices run from CHF 25,000 (titanium on rubber) to CHF 71,100 (gold on bracelet).

Worth watching

Today's three launches say the same thing by different routes: what separates these houses is no longer the complication itself but how energy and the hand are controlled. Grönefeld spends an entire calibre on securing constant torque; Vacheron gets a perpetual calendar down to 8.1 mm through a low frequency and a 40-year-old architecture; Breguet goes back to the rose engine to justify the price of a dial. The Quadrivium is worth following once independent measurements appear: a 7.5-second remontoire promises stable amplitude across the full 50 hours, and that is something you can verify.