Séverin Ronga (1857-1931), an Art Nouveau gold, sapphire and diamond pendant/brooch, circa 1900, of

Séverin Ronga (1857-1931), an Art Nouveau gold, sapphire and diamond pendant/brooch, circa 1900, of triangular outline, composed of three stylised floral sprays, the centre set with circular-cut diamonds and an oval sapphire, suspending a pear-shaped rose-cut diamond pendant, to a chain necklace, mounted in gold and silver, pendant 5.0 x 4.6cm, signed Ronga, French assay and partial maker's mark, chain length 42cm, unsigned, French assay mark for gold