Green Amethyst Quartz Sterling Silver Necklace This necklace features a Trillion cut Green Amethyst Quartz. The Amethyst Quartz is 8mm wide. The 1.3mm Flat Oval Cable Chain is Rhodium Plated 925 Sterling Silver for greater tarnish resistance. Polishing cloth for all jewelry included. Shipped in gift box. Amethyst is the birthstone for February.