PATEK PHILIPPE. A FINE AND RARE PLATINUM LIMITED EDITION AUTOMATIC ANNUAL CALENDAR WRISTWATCH WITH SWEEP CENTRE SECONDS, POWER RESERVE, MOON PHASES, SILINVAR SPRIOMAX BALANCE SPRING AND PULSOMAX ESCAPEMENT

The Advanced Research department at Patek Philippe is responsible for horological improvements and technical innovations, and one of their important developments in recent years is the creation of silicium, forged using the ultra-modern DRIE (Deep Reactive Ion Etching) process. Previously, hair springs were crafted from carbon steel, a material that is susceptible to magnetism, oxidation or rust and temperature variations, but modern-day silicium contributes greatly to the precision that Patek Philippe prides itself on, as it has non-magnetic, non-oxidisation properties, reduced mass, is not affected by temperature and has reduced sensitivity as it is three times lighter than conventional springs.

Following in the footsteps of this range's previous references, silicium is used in the references 5250, 5350 and finally 5450, the most current reference, the three most important components of the escapement - the hairspring, the balance wheel and the anchor or pallet fork - are now in silicium or Silinvar, as Patek Philippe has named it. With the use of the revolutionary Silinvar Spiromax spring, Patek Philippe has ventured one step closer to perfection - the spring is isochronous regardless of temperature, movement orientation or magnetic presence.

Offered by a distinguished and visionary Asian private collector, the present example is offered in virtually unworn condition with nearly no perceivable signs of wear visible with the naked eye, and comes complete with all accessories as the watch was delivered when new.