Art Deco diamond and colored stone brooch, French, circa 1920

The lobed oval plaque decorated with a flowering tree, the branches of calibré-cut onyxes bearing cabochon and calibré-cut demantoid garnets and cabochon amethysts representing blossoms, the pot of carved coral, within a ground of rose-cut diamonds, mounted in platinum, 1 small diamond missing, maker's mark, French assay marks.