Swiss gold watch set into 20 Dollar US coin dated 1904 Circa 1985

Gold coin watch with a skeletonized dial
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A very fine Swiss 18 carat yellow gold dress watch set in a U.S. 20 Dollar coin dated 1904, circa 1985. Double case, coin opening with a push piece concealed in the band, three body hinged inner case, graduated bezel. Skeletonized dial with black gold baton hands. Gilt, foliate hand engraved movement, straight line lever escapement, monometallic balance, self compensating flat balance spring, index regulator. Case and movement signed.
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Thickness: 5 mm
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Diameter: 35 mm
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Signed: Vacheron Constantin  Swiss
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Accompanied by the certificate of origin and a booklet