Vintage 18k Two-tone Gold Siberian Amethyst Diamond Pin BroochThis vintage 18k two tone gold brooch features a striking Siberian amethyst centerpiece in a cushion cut, framed by an ornate design of diamonds and additional amethyst accents. The central stone showcases the deep purple hue associated with fine Siberian amethyst, secured by four prongs, one of which does not sit flush as seen in the photos. Surrounding the main gem is a detailed openwork border of yellow and white gold, with pav set diamonds