Swiss gold tortoiseshell perpetual calendar watch Circa 1980

Gold tortoiseshell skeletonised watch
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A rare Swiss octagonal yellow gold and tortoiseshell skeletonised open faced perpetual calendar watch with moon phases, Royama, circa 1980. Engraved and skeletonised jewelled lever movement.
Skeletonised dial, yellow gold baton hands, subsidiary dials indicating day, month combined with leap year indication, date and moon-phases, octagonal yellow gold and tortoiseshell case, triple-stepped arched bow, sapphire crystal display back, case, dial and movement signed.
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Diameter: 42 mm
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Signed: Gérald Genta Genève