Two synthetic rings, a pair of gem set cufflinks and a pair of mother of pearl and diamond cufflinks, late 19th to early 20th century

One ring set with an oval synthetic ruby within a surround of rose-cut diamonds, size N; and one set with a cushion-shaped synthetic sapphire, size L^1/2, each with French assay marks; a pair of cufflinks set with circular-cut sapphires and rubies and cushion-shaped diamonds; and a pair of mother of pearl and diamond cufflinks and a similar pair of buttons set with onyx.