Daniel Roth’s perpetual calendar 2117 is certainly one of the most exciting watches of independent watchmaking as it brought together two of the greatest horological minds of the epoch to create: Daniel Roth and Philippe Dufour.

Roth started his eponymous brand in 1988 and rapidly set out on the task of creating a perpetual calendar. To help him he reached out to his fellow Vallée de Joux neighbor and friend Philippe Dufour who had just started his own journey as an independent watchmaker.

The goal the watchmakers wanted to achieve was to create the world’s first instantaneous perpetual calendar wristwatch whereby all indications would jump together precisely at midnight, rather than gradually as seen in more traditional executions.

The watch was first announced in Baselworld 1991, with a prototype featuring day and month indications via discs. However, the discs proved to be too heavy and too much energy was required for the discs to jump at the same time. The design was kept and the model became known as the C117 “semi instantaneous” perpetual calendar.

To achieve the original goal the discs were replaced by hands and the instantaneous perpetual calendar was finally launched around 1993-1994.

The present example in pink gold with black dial and gilt numerals is most probably a special commission piece as no numbers are featured on the watch, the brand name is not engraved on the case nor movement and the traditional guilloche rotor is replaced by an openwork engraved one with the initials EV.