First launched in 1978, the Quantime Perptuel by Audemars Piguet was the worlds thinnest automatic perpetual calendar. The reference 5548 was the first reference of this newly released perpetual calendar, birthing a category of watches which has taken on many different forms. Sources note that total production for the reference 25657* stands at 1821 watches, with just 128 in platinum, making this example fairly rare and not often seen on the market.

The lines of the original Quantime Perptuel were penned by Jacqueline Dimier, who is considered by some as the protg of the legendary. The perpetual calendar indications are laid out in an intuitive manner. The date and day are shown at 3 and 9 oclock respectively, with the months displayed at 12 oclock. A moonphase indication is placed at 6 oclock, with graduations for the moon position just above.

This platinum piece further stands out for its rare dial configuration. Whilst most examples of the Audemars Piguet Perpetual Calendar feature applied indices, this example features printed Roman numerals, imbuing this piece with an even more classic aesthetic. Though the change is subtle, it does give the watch a different feel and identity.Overall, the watch features platinum stick hands against a white background, and a typical double-stepped bezel. The three pushers are only visible when the watch is turned over. At 36mm in diameter and less than 8mm thick, the reference 25657 sits comfortably on the wrist. The caseback is engraved with the watch's individual case number.

Notably, unlike with earlier examples, such as similar reference 5548 pieces that feature Roman numerals, this reference 25657 has a complete moonphase, featuring an updated larger Audemars Piguet font, but also entering into the space where the 'VI' numeral would usually be. This updated look suggests that the piece was created slightly later on during the reference's production run. This is further confirmed when we note that the sub-dials on the watch are slightly recessed, with a complete, rather than semi-circle moonphase, as is present in earliest examples.

The watch is fitted with the ultra-thin, automatic calibre 2120/2800, derived from Jaeger-LeCoultres celebrated. The calibre 2120 was an initial project of Jaeger-LeCoultre in 1967, funded and contributed by Audemars Piguet, and famous for its adoption by Audemars Piguet, Patek Philippe and Vacheron Constantin.

Closer look

Condition

This Audemars Piguet Perpetual Calendar is in very good condition throughout. The case shows light superficial marks throughout, with very light scuffs on the lugs consistent with age and minimal wear over time. The dial and hands are free from any cause of concern and well preserved. The hallmarks and engravings on the caseback are crisp and well defined.

Warranty

The watch comes with a two-year warranty from A Collected Man, alongside a lifetime guarantee of authenticity.