The term 'ring material' can refer to a variety of materials used to make rings. One such material is 'ONION', which is a type of metal alloy composed of copper and zinc. Another material is 'CANVAS', which is a strong, durable fabric made from cotton or linen. Finally, 'sterling silver' is a type of silver alloy that is 92.5% pure silver and 7.5% other metals. All three materials can be used to make rings.