IWC Big Pilot's Watch Perpetual Calendar Ceralume: A Watch That Glows from Case to Strap
At Watches and Wonders Geneva 2026, IWC Schaffhausen introduced Ceralume®, its own luminous ceramic, in the Pilot's Watches collection. The first model to use it is the Big Pilot's Watch Perpetual Calendar Ceralume® (Ref. IW505801), limited to 250 pieces.
A watch with two faces
IWC calls it "a watch with two entirely different expressions". In daylight, the case, dial and strap show different shades of white and grey, with a mix of glossy and matte surfaces. In the dark, the whole watch glows a bright blue for more than 24 hours after being charged by light, while the numerals and hands appear as dark shadows against the glowing dial. Even the "Probus Scafusia" medallion on the rotor is luminous.
How Ceralume works
Ceralume was developed by IWC's engineering division XPL with the Swiss company RC Tritec, known for its Super-LumiNova® pigments. Ordinary white ceramic is made of zirconium oxide mixed with other metal oxides; for Ceralume, ceramic powders are blended with Super-LumiNova® pigments. The material absorbs sunlight or artificial light and releases it again as visible light, and the cycle can be repeated indefinitely. IWC compares it to a battery that stores light.
The difficult part was making the mixture uniform, because the raw materials have different particle sizes. IWC solved this with a special ball-milling process in a rotating drum that grinds the mix into a finer, more even powder.
Perpetual calendar and seven-day movement
The perpetual calendar, based on the design developed by Kurt Klaus in the 1980s, automatically accounts for the different lengths of the months and adds a leap day every four years. Four subdials show the date, day, month and moon phase, and a four-digit year appears between 7 and 8 o'clock. The Double Moon® display shows the moon as seen from both the Northern and Southern Hemispheres and deviates by just one day in 577.5 years. Learn more about its inventor in IWC legend Kurt Klaus.
The 46.5 mm case houses the IWC-manufactured calibre 52616 with Pellaton winding and near wear-free ceramic components. Its power reserve is 168 hours, or seven days. The movement, decorated with circular graining and blued screws, is visible through a sapphire case back. The white rubber strap also contains Super-LumiNova® pigments.
Specifications at a glance
- Reference: IW505801, limited to 250 pieces
- Case: 46.5 mm, Ceralume® luminous ceramic, sapphire case back
- Movement: IWC calibre 52616, automatic, Pellaton winding, 168-hour power reserve
- Functions: perpetual calendar with date, day, month, four-digit year and Double Moon® moon phase
- Dial and strap: white, luminous; white rubber strap with Super-LumiNova®
IWC's announcement did not include a price. See also our IWC complications and Pilot's Watches catalogues.
Source: IWC Schaffhausen press release, 14 April 2026. More about the brand: IWC Schaffhausen.
