The way the delicate fawn brown dendrites in this agate pick up the brown of the host stone in this dramatic blue boulder opal, means they are meant to be paired together in a ring. I've wrapped them each in 22k gold and set them on oxidized silver and added a rich cluster of brown tourmalines and lapis lazuli on 14k pins between. The simple band measures a size 7 and can be enlarged up to a 7 3/4.