Swiss gold watch with experimental movement Circa 1876

Gold open faced lever pocket watch
–
Extremely rare and technically highly interesting Patek Philippe gentlemen’s watch with experimental movement no. 57107, Genève, circa 1876.
An 18 carat gold, matching number 57107 on the case and movement, dome signed and numbered, case with Patek Philippe punch.
Precision lever movement with special and experimental winding system according to the invention of Courvoisier, moustache lever.
Undamaged enamel dial, blued steel hands, good condition.
–
Diameter: 46 mm
–
Weight: 77 g
–
Signed: Patek Philippe  Genève
–
Patek Philippe produced some of these movements only for a short period of time from around 1875 to 1877, at least in four different “experimental” versions. The other two watches with this movement are depicted in Martin Huber & Alan Banbery “Patek Philippe”. This variant is the rarest and most complicated version of this limited series.