Very early, interesting gold open faced lever watch Circa 1868

Gold open faced lever watch with rare calibre by Patek Philippe
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A very early, interesting Swiss 18 carat gold open faced pocket watch, circa 1868. Made for Palmer Bachelders & Co, Boston. Very rare bar movement with key winding, large balance with gold screws and moustache lever. White enamel dial with Roman numerals and filigree steel Breguet hands. Engine turned case, reeded mid section. Cuvette signed and numbered.
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Diameter: 47 mm
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Weight: 82 g
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Signed: Patek, Philippe & Co Geneva