Six romantic perpetual calendar watches that are particularly noteworthy

With the exception of a once-in-a-century "exception," as long as the watch doesn't stop, the perpetual calendar automatically distinguishes between full and short months and adjusts the date when the month changes. This romantic mechanism has been around for at least 200 years, and today we'd like to introduce six particularly outstanding models from our own unique perspective.

Audemars Piguet
"Royal Oak Perpetual Ultra-Thin Automatic"

　Following a teaser at SIHH 2019, Audemars Piguet unveiled the production Royal Oak Perpetual Ultra-Thin Automatic in June. It's the world's thinnest automatic perpetual calendar watch, measuring just 6.3mm thick. The 41mm satin-brushed titanium case features an anti-reflective sapphire crystal and a polished platinum bezel, reminiscent of last year's Royal Oak Jumbo Extra-Thin (15202IP). The satin-brushed titanium bracelet is fitted with platinum links and a titanium folding clasp.

Special Points

　Aside from winning the Aiguille d'Or (Golden Hand Award) at the 2019 Geneva Grand Prix, the Caliber 5133 is also notable for its thickness of just 2.89mm (!). This is made possible by consolidating the movement's module from three layers to one. The technical skill required to reduce a three-layer structure to a single layer while maintaining efficiency is no mean feat. Audemars Piguet spent five years researching and developing this solution.

Baume & Mercier
"Clifton Baumatic Perpetual Calendar"

　The Baume & Mercier Clifton Baumatic Perpetual Calendar is based on the Baumatic movement introduced last year and incorporates a Dubois-Dépraz perpetual calendar module. The Baumatic movement boasts a power reserve of approximately five days, high magnetic resistance, and a long service interval of seven years. It also features a date rewind function. The 42mm case is crafted from satin-finished 18K rose gold and is just 12.1mm thick. It features sporty curved lugs and a domed sapphire crystal.

Special Points

　This model uses an affordable modern movement like the Baumatic, yet is extremely rare in that it also features a perpetual calendar mechanism. This wonderful movement boasts a long power reserve, anti-magnetic properties, high precision, and long maintenance intervals, all housed in a classically designed rose gold case, and is priced at just 259 yen (excluding tax).

Blancpain
"Villeret Perpetual Calendar 6656"

　In 2019, Blancpain introduced the Villeret Perpetual Calendar 6656 in platinum, available exclusively through more than 30 official boutiques worldwide. This limited edition of 88 pieces features a well-balanced case measuring 40mm in diameter and 10.7mm thick. The attractive sunburst blue dial features subdials at 3, 9, and 12 o'clock, as well as a moon phase display at 6 o'clock. A central seconds hand glides across white gold Roman numerals. The movement is powered by Blancpain's in-house automatic caliber 5954. The movement's balance spring is made of silicon, extending the power reserve to approximately 72 hours. The rotor is crafted from solid gold, as befits a luxury watch.

Special Points

　What makes this high complication so special is the ability to adjust the calendar mechanism and moon phase by pressing a lever under the lugs on the case back, developed by Blancpain, which adds a touch of elegance to the watch's aesthetic design.

Jaeger LeCoultre
"Master Grand Tradition Gyrotourbillon Westminster Perpetual"

　At the 2019 SIHH, Jaeger-LeCoultre unveiled the latest multi-axis tourbillon, the Master Grande Tradition Gyrotourbillon Westminster Perpetual, capturing the attention of the entire venue. Key highlights include a perpetual calendar, a minute repeater with Westminster chimes, and a constant-force mechanism that provides stable power regardless of the mainspring's winding state. The exterior is crafted from a 42mm white gold case with sandblasted case sides and a highly polished finish. The deep blue Grand Feu enamel dial (a silver dial is also available) is accented by a date ring with a grained engraving. The perpetual calendar display—day, month, and date—is expertly arranged to blend seamlessly with the enamel dial.

Special Points

　Stéphane Belmont, Director of Heritage at Jaeger-LeCoultre, said: "This is the pinnacle of our collection, incorporating complex mechanisms such as the Gyrotourbillon, which we have patented over the years, as well as a minute repeater and a perpetual calendar. At the same time, we have managed to keep the size compact enough to ensure comfort and elegance."

Parmigiani Fleurier
"Trick Perpetual Calendar Retrograde"

　In 2019, Parmigiani Fleurier introduced the Toric Perpetual Calendar Retrograde, the most complex model in the Toric collection. It features a retrograde pointer date display and a highly accurate moon phase display that deviates by just one day every 122 years. The eye-catching moon phase display at 6 o'clock, displayed with two hemispheres and a starry aventurine disc, is a striking feature. The Toric collection's signature curved case and hand-finished coin-edge bezel are also featured. The 18K rose gold case measures 42.5mm in diameter and 12.1mm thick, making it a comfortable fit. The crown is adorned with a blue cabochon. The dial is available in two finishes: a slate gray dial with rice-grain guilloché or Parmigiani's signature white-grain finish. The transparent case back reveals the in-house automatic caliber PF333.

Special Points

　The adjustment of the months, including leap years, is automatically performed by a cam with a planetary gear. The moon phase is highly accurate, with an error of only one day every 122 years, and is controlled by a gear train mounted in the same module as the date calendar.

Vacheron Constantin
"Traditional Twin Beat Perpetual Calendar"

　Vacheron Constantin's new perpetual calendar model, unveiled in 2019, features a function that pushes the boundaries of permanence more than any of their previous models. The Traditionnelle Twin Beat Perpetual Calendar features a patent-pending "mode selector" that allows users to select the frequency of the movement. The watch's frequency can be switched between an active mode of 36,000 vph and an energy-saving mode of 8640 vph.

Special Points

　It is a very modern watch, released by the world's oldest watch manufacturer, and features a practical mechanism that users can be proud of.