Accompanied by Patek Philippe Extract from the Archives confirming production of the present watch with amagnetic movement 27-AM 400 in 1962 and its subsequent sale on 8 February 1963 and presentation box.
To the best of our knowledge, this watch has never been offered at auction before and is the first reference 570 in gold with calibre 27-AM 400 and original black dial known to exist and furthermore to appear in public to date. It is in addition one of only two examples of reference 570 fitted with an anti-magnetic movement 27-AM 400 known to date, a previously unknown combination.
Rather sensationally, the second example is also offered in this auction, lot 219, cased in pink gold and with silvered dial, consequently rendering the two watches unique pieces.
Fresh to the market, the present watch furthermore impresses with its very good condition, preserving the sharp lines of the case, and attractive black dial.
The large Calatrava model reference 570 was introduced into the market in 1938, featuring either subsidiary or sweep centre seconds. The present watch is from the first series made with subsidiary seconds but with the extremely unusual particularity of a 27-AM 400 anti-magnetic movement, normally reserved for Patek Philippe's "Amagnetic" watches such as references 2570/1 and 3460. The amagnetic calibre 27-AM 400 was launched in 1960 and is an improved version of the 1958 calibre 12'''400, fitted now with a Gyromax balance and free sprung self-compensation Breguet overcoil hairspring.
"Amagnetic" watches were designed for use in areas of high electro-magnetic fields such as in laboratories or electro-engineering. It can therefore be assumed that the original owner of this watch ordered it purposely with an amagnetic movement, as confirmed by the Extract from the Archives.