Swiss 18 carat gold open faced calender watch Circa 1810

Gold calender watch by Louis Duchène et Comp.
–
A Swiss gold key wind calendar pocket watch by Louis Duchène & Comp, circa 1810. Gilt full plate fusee verge movement, pierced and engraved balance bridge with polished steel coqueret, silver regulation disc with blue indicator.
White enamel dial, black Arabic numerals, black outer minute divisions, winding aperture at 2 and gilt hands. 18 carat polished open faced consular case.
Signed movement.
–
Diameter: 49 mm
–
Weight: 79 g
–
Signed: L’s Duchène et Compagnie
–
Louis Duchene et Cie. Geneva late 18c.-c. 1810. Examples of gold watches by Ls. Dechene are in the Carnegie Museum and the Metropolitan Museum of Art, New York.