Vintage Sterling Silver Amethyst Glass Floral Brooch

Very large sterling silver brooch. Has a huge piece of faceted amethyst color glass which appears to be a flower/flower bud. The stem and leaves are gold tone but the gold tone is fading. I was surprised that this is sterling silver because there are no markings on it, but it is definitely sterling silver. The glass is in great condition no chips. Just under 4” x 2.5”. unique piece