Perpetual Calendar Chronograph, diamond-set

The perpetual calendar chronograph is the reference family Patek Philippe has kept in continuous production longer than any other manufacture has kept anything. Day, date, month, leap year and moonphase, all governed by a mechanism that will not need correcting until 2100, married to a chronograph.

On this execution the dial is black and the applied indices are diamond, with a baguette-cut bezel that changes the character of the watch entirely. A steel-bezel perpetual chronograph is a connoisseur's watch. This one is a statement, and it is aimed at a specific buyer who wants both the complication and the presence.

Read the dial the way a specialist reads it. Day and month sit in twin apertures below twelve. Small seconds and the thirty-minute counter oppose each other. The date runs around the perimeter of the subsidiary register at six, with the moon in its aperture. The tachymetric scale rides the flange.

Nothing here is added. Every marking corresponds to a function, and the balance of the layout is why this dial has survived, essentially unchanged in architecture, across generations of the reference.

These are traded quietly. Diamond-set complicated Pateks rarely appear in public sales in Asia, and when they do, condition of the bezel setting matters as much as the movement.