Dufour, Ceret & Cie, Ferney, France. A tri-colour gold key wind open face pocket watch with enamel portrait miniature

Dufour, Ceret & Cie, Ferney, France. A tri-colour gold key wind open face pocket watch with enamel portrait miniature
Date: Circa 1770
Movement: Gilt full plate fusee verge, 3-arm balance, pierced balance bridge, silver regulation, No.1601
Dial: White, black Roman numerals, black outer minute divisions with Arabic numeral five minute markers, winding aperture at 2, stone set decorative hands
Case: Consular with portrait miniature of Marie Antoinette to back set within elaborate enamel and stone set borders
Signed: Case stamped GA, movement signed
Size: 40mm