Swiss 18K gold keyless chronometer dress watch Circa 1910

Gold open faced lever pocket watch 
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A very fine and rare Swiss, 18K yellow gold keyless chronometer dress watch, circa 1910. With Guillaume compensation balance. A solid, polished case, hinged gold cuvette with inscription. Double-sunk, white enamel dial with gold Breguet numerals, outer minute track, sunk subsidiary seconds dial. Blue steel Breguet hands. A rhodium-plated movement, 19 jewels, straight-line lever escapement, Anibal-brass Guillaume balance, blued steel Breguet balance spring, index regulator. Dial and case signed.
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Thickness 11 mm
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Diameter: 51 mm
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Signed: Paul Ditisheim  La Chaux-de-Fonds