Very interesting piece. Appears to be a very old handmade ring with an Islamic seal set and hand carved in a gate or possibly carnelian. I have no information about it. It is a very tarnished silver with a nice patina. It is in very good condition except for a very tiny chip broken off the agate. You can see this in one of the pictures. There is an interesting cross mark made in the back of the ring on the outside on the shank. I am unsure of age but it could possibly be 1800s?