A very fine two-colour 18ct yellow and white gold open-faced keyless lever one-minute tourbillon watch with state-of-wind indication and presentation box

19’’’ half-plate Victorin Piguet ébauche, damascened decoration, going barrel, ruby jewels, lever escapement, Guillaume balance, blued steel hairspring with Breguet overcoil, precision micrometer regulation, three-arm polished steel Le Sentier-type tourbillon cage mounted on a one-minute rotating carriage, signed, numbered and detailed to backplate No. 3102 Regulateur à Tourbillon, Brevet Breguet du 26 Juin 1801 

silver engine-turned dial, clous de Paris guilloché patterned centre, satin finished chapter rings for hours with black Roman numerals and pearled minute track, twin subsidiary seconds rings, the outer with Arabic/dot 5-second divisions, the inner pearled, crescent-form sector for state-of-wind indication from 0-30, all chapters and sector with crémaillère borders, rectangular cartouches signed and numbered Breguet 3102

18ct yellow gold satin finished case with white gold rims and bow, milled yellow gold band, satin finished yellow gold hinged back with decorative perlage to interior, glazed exhibition cuvette, French eagle’s head assay marks to inside back, bow and pendant

Measurements

diameter 52mm

depth including crystal 13.3mm

weight 134.5g

Accompaniments

with a red morocco leather presentation case numbered 4438 to lid, the back dyed green and having gilt lettered roundel signed Breguet & Comp^ie quai de l’Horloge du Palais, No. 39 à Paris. Turquoise velvet fitted interior, silk lined lid concealing certificate compartment and a Breguet 250th anniversary certificate