The IWC-manufactured 51950 caliber features a Pellaton winding system, which generates a power reserve of seven days in the mainspring. The move ment, with its solid gold oscillating weight, can be admired through the sapphire glass case back.
The Portugieser is one of IWC Schaffhausen’s most emblematic collections. Its origins date back to Reference 325 from the late 1930s when two Portuguese merchants commissioned a large wristwatch with the precision of a pocket watch. This timeless watch continues to define the aesthetic of the collection today. Over the decades, the Portugieser has also welcomed many high watchmaking complications. With this new model, IWC continues this tradition while introducing a distinctive new dial color.
Limited to 50 pieces, the Portugieser Perpetual Calendar Tourbillon (Ref. IW504509) features a 45-millimeter case crafted from platinum. Platinum is among the rarest, purest and most precious metals used in watchmaking, appreciated for its exceptional durability and distinctive, silvery-white sheen. The platinum case is paired with a striking purple dial finished with a sunray pattern. The applied Arabic numerals, a recurring design element of the Portugieser, are rhodium-plated and individually set by hand. The characteristic minute scale places the markers between an inner and outer circle, reminiscent of a railway track. The leaf-shaped hands are also rhodium-plated. The watch is fitted with a hand- colored black alligator leather strap crafted by the Italian leather artisans from Santoni.
Two Complications in One Watch
This Portugieser brings together two high complications: a perpetual calendar and a flying minute tourbillon. The flying minute tourbillon is positioned at 12 o’clock on the dial. Comprising 82 parts and weighing only 0.635 grams, this delicate mechanism is among the most complex in watchmaking to assemble and regulate. Originally conceived to counteract the effects of gravity on the oscillating system, the tourbillon enhances precision by placing the pallet lever and escape wheel within a small rotating cage. This cage completes one full rotation per minute, while its continuous motion creates a captivating visual spectacle.
Developed by the legendary watchmaker Kurt Klaus in the 1980s, the perpetual calendar displays its information across three subdials. The date appears at 3 o’clock, the day of the week at 9 o’clock, and the month and perpetual moon phase displays are combined at 6 o’clock. Thanks to a reduction gear train with two intermediate wheels, the moon phase will deviate by just one day after 577.5 years. The calendar is mechanically programmed to account for the varying lengths of the months and automatically adds a leap day every four years at the end of February. All displays are synchronized and can be advanced simply by turning the crown.
Complex Manufacture Movement with 447 Parts
Both complications are driven by the IWC-manufactured 51950 caliber, a highly complex movement comprising 447 individual parts. The integrated Pellaton winding system harnesses the rotor’s movement in both directions to wind the mainspring, building up a power reserve of seven days (168 hours) in a single barrel. The balance wheel, fitted with a Breguet hairspring, oscillates at a frequency of 2.75 hertz (19,800 vibrations per hour). The movement is elaborately finished with Geneva stripes and features a solid gold oscillating weight. It can be admired through the sapphire glass case back.
