Art Deco Onyx, Enamel and diamond desk clock, Cartier, Paris, circa 1920

The circular dial applied with translucent enamel over a guilloché ground, the hands set with rose-cut diamonds, the white enamel chapter ring featuring gold Roman numerals and florets, within a black onyx arched panel, the base accented with 2 rose-cut diamonds, gilt metal easel at the back, dial signed Cartier, movement signed European Watch & Clock Co., Inc., France 1317, case numbered 534, dial possibly re-finished, onyx cracked. 

The Jewels and Objects of Vertu of The Honorable Clare Boothe Luce, sold by Sotheby's, New York, April 19, 1988, lot 602.