IWC Portugieser Eternal Calendar

In watchmaking, the complexity and prestige of calendar complications enhance the value of a timepiece. The simplest, adjusting for months shorter than 31 days, is the least prestigious. The pinnacle of this technology is the secular perpetual calendar, such as the one featured in IWC's Portugieser Eternal Calendar, which reduces the need for manual corrections by accurately accounting for leap year anomalies over a 400-year cycle. This includes correctly identifying which centennial years are leap years, a refinement not found in standard perpetual calendars.Additionally, the Portugieser Eternal Calendar includes an advanced moonphase mechanism that achieves extraordinary precision, deviating only a single day every 45 million years. This mechanism was developed after simulating over 22 trillion gear configurations. Together, these features not only align perfectly with the Gregorian calendar but also showcase IWC's commitment to high-precision engineering, offering a sophisticated and rare experience for watch collectors.The 44.4mm case with a height of 14.9mm is made of platinum with a mix of polished surfaces and brushed casebands. Encased in the iconic Portugieser style, the Eternal Calendar introduces a contemporary element with its glass dial, which reveals the underlying calendar mechanisms. This is achieved through the use of a sapphire bridge within the calendar module, a first for IWC in employing this material structurally in a movement. This extensive application of sapphire not only showcases the movement's intricate technicality but also brings the inner workings visibly to the forefront, enhancing both the watch's aesthetic and mechanical allure.On the flipside is a sapphire exhibition caseback that allows a view into the inner workings of the mechanical movement. It features blued screws, Geneva stripes on the bridges, milled anglage, and perlage on the main plate are meticulously executed. The rotor, crafted from 18-carat gold, also includes an intricately cast IWC emblem.The original Kurt Klaus calendar module is recognized for its classical approach, utilizing a traditional 48-month cam and grand lever while innovatively eliminating the need for case correctors. Instead, all adjustments to the calendar are made via the crown, though this system only allows settings to be advanced forward.Mechanically, the system tracks years, months, dates, days, and the moon phase in unison. Adjustments are made simply by turning the crown, which also advances the day of the week and moon phase. Over time, the module has seen various enhancements, maintaining its core design while incorporating safety features to prevent misuse. Notably, the accuracy of the moon phase display has improved significantly; originally set to the industry standard deviation of one day every 122 years, a revision in 2003 improved this accuracy to one day every 577.5 years. Water-resistance can reach up to 50 meters (164 feet).Time is exhibited on a white lacquer dial with applied Arabic numerals, which features a double-box glass sapphire crystal. Therefore this design highlights the use of glass not only for protection but also for aesthetic purposes because the dial is crafted from glass, which lends a translucent quality to certain features, such as the Double Moon™ phase indicator.The layout of the perpetual calendar is relatively standard, featuring central hour and minute hands. It includes a moonphase indicator at the 12 o'clock position with a scale and hemisphere display. The 3 o'clock position houses a sub-dial for the power reserve and date, while the 6 o'clock position displays the months. The year is shown between 7 and 8 o'clock, and at 9 o'clock, there's a small seconds dial along with the days of the week.

IWC Portugieser Eternal Calendar

The “IWC Portugieser Eternal Calendar” (Ref#: IW505701) is powered by the in-house self-winding mechanical movement, caliber 52640 with 54 jewels, 386 parts, and 28,800 vph. It comes equipped with a perpetual calendar, a moon phase display, and a Pellaton winding system. Power reserve can last up to 168 hours, when fully wound.Mounted on the watch is a Santoni black alligator scaled leather strap with tone-on-tone stitchings, secured to the wrist by a platinum folding clasp. For more up to date information visit the official IWC Schaffhausen website here.

IWC Schaffhausen, IWC, Portugieser, Perpetual Calendar, Eternal Calendar, Watches & Wonders, Luxury Watches