These are really beautiful napkin rings. We used them to safely display Christmas ornamanets by sitting in the hole. They have a diamond or square pattern. It is 1 15/16th inches "diameter" and 3/4" deep. I don't see or feel any roughness to indicate a chip or cracks. I am not 100% sure what the material is, likely pressed glass but it does have some weight to it. Please see photos as they are part of the description
