A gold openface tourbillon watch, Comor, circa 1980

18k, three-quarter plate nickel lever movement, two arm glucydur balance with timing screws, 21 jewels, tourbillon mounted under a sapphire glass functioning as a bridge holding the pivot of the upper end of the axle in a ruby stone, the plates engraved with geometric design, white enamel dial, roman numerals, subsidiary seconds, slender openwork hands, the case with reeded band and glazed back, dial signed.

Comor Watch Co. was founded by Adolf Benz in La Chaux-de-Fonds in 1977. Adolf Benz, a collector, collaborated with watchmaker George Thomas to design a tourbillon of which they produced 10 pieces. The present lot, signed Comor, is one that was produced after the limited edition was finished and under the auspices of the Comor Watch Company.

For a tourbillon by Benz and Thomas, see Sotheby's, New York, June 4 and 5, 1984, lot 222.