Plate brooch in platinum 850 thousandths with openwork silhouette, set with eighty-five old brilliant-cut diamonds, the main one approx. 0.50 ct, highlighted with chalcedony cabochons in random shades ranging from white to onyx black (one missing), secure pin. French work from the Art Deco period. HL master goldsmith's hallmark (partially legible). Estimated total diamond weight: 3 ct Height : 2.2 cm - Width : 6.7 cm - Gross weight : 11.3 g