Authentic Handmade Hopi rings are made with sterling silver and are carefully hand crafted by Hopi Silversmiths. They typically use an overlay technique that starts with 2 flat pieces of silver. The base or bottom piece is left solid and as is. The second piece of silver will be used to cut detailed ring designs into by the Hopi artist. After the cutting is finished they put the second piece of silver over the first to make incredible ring designs similar to the pictures below. The Hopi tribe is well known for perfecting the overlay technique in their handcrafted rings.
Most people can't really appreciate the craftsmanship a Hopi artisan puts into their jewelry until they see the artistic process from start to finish. Hopi Rings vary so much it's almost impossible to explain the design variations.
Posted below are three Hopi ring pictures from Hopi Silversmiths: