Thomas Mudge produced the oldest known perpetual calendar in 1762. Patek Philippe followed in 1925 with a perpetual calendar wristwatch based on a ladies’ pendant watch. Breguet created the first perpetual watch with a true wristwatch movement in 1929.

However, it was not until 1955 that the leap year indication was brought to a wristwatch by Audemars Piguet in the reference 5516. Prior to that, all perpetual calendar mechanical wristwatches had the day, date, and month indications – not the leap year.

Having said that, Audemars Piguet is clearly recognized as a leader and innovator in the Perpetual Chronograph field, however, it is not the perpetual calendar equipped caliber 5134 movement that is new. Although, it was in 2015, when the larger 41 mm perpetual calendars in steel and pink gold models were introduced, with the enlarged movement (based on caliber 2120).

The highlight is that the iconic Gérald Genta-designed Royal Oak case, bezel, and bracelet are now available in hand-finished black ceramic. In addition to creating a new look for the brand’s most famous model, the material is 9 times harder than steel making it virtually scratch proof, extremely resistant to high temperatures, thermal shocks, and aging.

It takes six hours to machine, polish, hand-finish, assemble and quality check a stainless steel Royal Oak bracelet, whereas the ceramic bracelet requires 5 times as much time to complete – 30 hours.

The Royal Oak Perpetual Calendar in full black ceramic displays the date, month, a photo-realistic astronomical moon phase indication, the week of the year displayed on the dial’s outer chapter ring, and the leap year indication, with black counters against a slate-gray “Grande Tapisserie” dial.

The case measures 41 mm in diameter, features a sapphire caseback and is water-resistant to 50 meters. It is worth noting that the AP folding clasp is crafted in black titanium not ceramic.

The retail price of the new Royal Oak Perpetual Calendar in black ceramic is $93,900. To put that number in context, the existing steel and gold Perpetual Calendars are priced at $60,900 and $95,700, respectively.

It will be interesting to see black ceramic utilized for future Royal Oak models. I can already imagine a chronograph or time-only Royal Oak in black ceramic! (Ref. 26579CE.OO.1225CE.01)