In some of my old reference materials, I saw a squash blossom set whose construction was close to this ring. So I think this ring was separated from a similar set. After purchasing the ring, I showed it to a trader that had a storefront in Walnut Creek, Ca. He expressed an interest in buying the piece indicating these cabs were Bisbee. Opinions? I kept the ring, hating to think it would be raided for the rocks. The cabochons measure about 3/8" x 5/8" , the ring face 2 1/2" x 7/8" No hallmarks
The stones are nice. When they are this little it is always difficult to identify. They could be something like Blue Diamond.