F.P. Journe Quantième Perpétuel Black Label Platinum 40 MM - Black Leather Strap - Black Dial - Quantième Perpétuel Black Label

40 mm, Platinum case. The F.P.Journe Quantième Perpétuel (Perpetual Calendar) displays the exact date by automatically taking into account the variable length of the months and leap-year cycle. It also displays the day, month, and often the moon phases. To accomplish this watchmaking feat, the movement must have a mechanical "memory" of 1461 days or four years. The mechanism is usually based on a differential gear system from the hour wheel and includes several hundred components, cogs, gears, levers, and rockers. Despite their name, perpetual calendars will have to be corrected by one day on 1 March 2100, not through any fault of the mechanism but due to the Gregorian calendar, which rules that this year, as three centennial years out of four, will not be a leap year.

F.P. Journe Quantième Perpétuel Black Label Platinum 40 MM - Black Leather Strap - Black Dial - Quantième Perpétuel Black Label