MEXICAN STERLING SILVER AND ENAMEL MASK PENDANT ON BLACK ONYX, MALACHITE AND STERLING BEAD NECKLACE.By Margot de Taxco, Circa 1960's-early 1970's. Pendant fashioned as stylized profile of native with black enamel overlay and iridescent blue, green and yellow mosaic-like enamel. Pendant, L: 3 1/2"; necklace, L: 22" Estimate $250-350