English 18 carat gold and enamel pair cased watch Circa 1780

Gold and enamel pair cased watch with two portraits
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An English gold and enamel pair cased watch, circa 1780, gilt metal verge movement, ruby endstone, pierced and engraved balance cock with scrolls.
White enamel dial, Roman numerals, outer minute track with Arabic numerals, gold outer case engraved with crown and foliate borders, two kidney shaped panels with polychrome enamel portraits of a noble couple, dial and movement signed, case with MM makers mark.
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Diameter: 39 mm
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Signed: Pierre Reguillard
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Probably English