Amethyst Adjustable Ring Simple and delicate, this ring showcases two 4mm purple amethyst stones. The open face of the ring design allows it to be slightly adjustable.Created out of Argentium silver, which is like sterling silver but formulated to be tarnish resistant (It is still marked at .925 Silver), and two small delicate bezels for the stones, this ring is lightweight and wonderful. Don't see the birthstones or gemstone you want? Send a quick message to seller and I'll get you a quote and availability! These stones make great stacking rings, get them in several colors! Rings are made to order in whole and half sizes 4-16, the band of the ring is 1.6mm thick.