Patek Philippe Perpetual Calendar Chronograph 1518

A RARE YELLOW GOLD PERPETUAL CALENDAR CHRONOGRAPH WRISTWATCH WITH REGISTERS AND MOON PHASES REF 1518 MVT 863033 CASE 631489 MADE IN 1943

Patek Philippe A RARE YELLOW GOLD PERPETUAL CALENDAR CHRONOGRAPH WRISTWATCH WITH REGISTERS AND MOON PHASES REF 1518 MVT 863033 CASE 631489 MADE IN 1943 yellow gold, leather diameter 35 mm , • cal. 13''' manual winding lever movement, 23 jewels • silvered dial, applied yellow gold Arabic numerals and dot indexes, outer minute track with 1/5 seconds divisions, outermost tachymeter scale calibrated for 600 units, subsidiary dials for constant seconds, 30-minute register, and date combined with moon phases, twin apertures for day and month • 18k yellow gold case, snap-on back • case, dial and movement signedPatek Philippe, Estimate 100,000 - 150,000 CHF , Sold , Patek Philippe A RARE YELLOW GOLD PERPETUAL CALENDAR CHRONOGRAPH WRISTWATCH WITH REGISTERS AND MOON PHASES REF 1518 MVT 863033 CASE 631489 MADE IN 1943 yellow gold, leather diameter 35 mm , • cal. 13''' manual winding lever movement, 23 jewels • silvered dial, applied yellow gold Arabic numerals and dot indexes, outer minute track with 1/5 seconds divisions, outermost tachymeter scale calibrated for 600 units, subsidiary dials for constant seconds, 30-minute register, and date combined with moon phases, twin apertures for day and month • 18k yellow gold case, snap-on back • case, dial and movement signed , Accompanied by a Patek Philippe Extract from the Archives. The Ref. 1518 played a critical role in the development of Patek Philippe's complicated wristwatches. Together with Ref. 1526, it was the first perpetual calendar wristwatch ever produced by the company in series. It is recognized that the introduction of Ref. 1518 greatly contributed to the manufacturer's dominant position in the Swiss watchmaking industry. Indeed, perpetual calendar wristwatches produced in series were almost exclusively a Patek Philippe commodity for four decades (other manufacturers tending not to list or distribute the complication other than for special orders). The influence of the Ref. 1518 can be seen in all the series-produced Patek Philippe perpetual calendar chronographs that came after it (Refs. 2499, 3970, 5970, 5270). Even though the case design changed in the references that followed, the basic dial layout remained the same. Similarly, the functions of the movement have not changed in 70 years. The Ref. 1518 was equipped with a Valjoux calibre 13Q (13 130Q), which was first upgraded and finished to the highest standards for the time in Patek Philippe's workshop. Then, Victorin Piguet was employed to modify the under-dial work and incorporate the perpetual calendar function. It was not until 1985 that Patek Philippe replaced the Valjoux for a Lemania calibre in its perpetual calendar wristwatches. With the new Ref. 5270, the Lemania caliber was replaced with the fully in-house calibre CH-29-535 PSQ. From 1941 to 1954, a total of 281 Ref. 1518 wristwatches were made, an incredibly small production run by today's standards, with an average of just 20 watches per year.