An unusual Art Deco carved hardstone, enamel and diamond pendant, 1930s, of circular outline,

An unusual Art Deco carved hardstone, enamel and diamond pendant, 1930s, of circular outline, centring on a spray of leaves and flowers in multicoloured carved chalcedony, rock crystal and opal, accented with circular-cut diamonds, on a ground of translucent blue enamel, the reverse with the same engraved floral design, within a frame of frosted rock crystal, to a stepped bail of stepped design, mounted in platinum, length 5.5cm including bail