12 Vacheron Constantin A fine and rare, Les Complications, perpetual calendar moon phases, automatic wristwatch in yellow gold, with Certificate of Origin, reference 43031.

Estimate: € 15.000 –⁠ 30.000

• Model Les Complications
• Year 1987
• Reference 43031
• Case Material 18K yellow gold
• Case Number 574'651
• Bracelet Material Leather strap
• Movement Automatic, cal. K1120, 36 jewels
• Movement Number 709'273
• Dimension 36mm Diameter
• Signed Case, dial and movement
• Accessories Accompanied by Vacheron Constantin Certificate of Origin dated August 11th 1987 and stamped Sautter Lugano and service dated 29th April 1997.

For connoisseurs, the four digits that identify the calibre 1120, immediately evoke something rather special. Born in 1968 as Jaeger-LeCoultre’s calibre 920, it was, at the time, a technical mic drop: the thinnest full-rotor automatic movement ever made. Vacheron Constantin not only adopted this ébauche, it elevated it. Finished to Geneva Seal standards and adjusted to the maison’s philosophy of understated excellence, the caliber 1120 became a cornerstone of its high complications. In the present watch, it serves as the base for a perpetual calendar, a feat that deserves a moment of appreciation. To stack day, date, month, leap year and moon phase indications onto an already ultra-thin automatic architecture, without turning the watch into a dinner plate, requires genuine technical finesse. And yet, nothing about this piece shouts. The dial is composed with classical restraint: neatly proportioned subdials, a poetic moon phase aperture, and slender applied markers that allow the complication to breathe. The yellow-gold case remains impressively preserved, with strong proportions and a crisp hallmark to the exterior of the caseback, the sort of detail that seasoned collectors quietly look for. It is slim, sophisticated and mechanically distinguished; a perpetual calendar that whispers rather than proclaims, powered by one of the most important automatic calibres of the 20th century.