A pair of Art Deco onyx and diamond cufflinks and a pair of collar studs, France, early 20th

A pair of Art Deco onyx and diamond cufflinks and a pair of collar studs, France, early 20th century, comprising: a pair of cufflinks, each end composed of a circular section of onyx set with a circular-cut diamond held in place by prongs set with rose-cut diamonds, mounted in gold, diameter of each end 1.3cm. French assay marks for 18ct gold; a pair of matching collar studs, diameter 1.0cm each, French patent marks; together with two additional collar studs set with onyx and diamonds