An Extraordinary half pearl and diamond set quarter-repeating ring watch with visible diamond-set balance with its original box case. 18k pink gold, rectangular-shaped case with cut corners, the bezel set with half pearls, diamonds and gold pearls. Slide for repeating mechanism, push back with apertures for winding and hand-set reeded shank with triangular-shaped half pearl-set shoulders. The dial is an enamel eccentric dial with Arabic numerals, signed, blued Breguet hands. Upper part with a polished disc with four curved diamond-set arms illustrating a visible balance. Rectangular shaped movement, frosted, gilt, 2 hammers, 1 bell, 2 barrels for going and striking train and cylinder escapement. This piece is one of five known quarter repeating ring watches. Achard & Fils was a fine watch maker based in Geneva founded in 1796 by George Achard under the name Achard & Cie. Later the company changed its name to Achard & Fils which became well known for its enamelled watches until the company dissolved in the 19th Century. See the book from the Patek Philippe Museum page 73.