Natural Turquoise Ring in Sterling Silver Size 6 1/4

Vintage Navajo sterling silver ring that is set with a nice bi-colored natural turquoise stone that has spots of black chert. 

Size 6 1/4 Face measures 3/4" by 5/8". Hand formed shank and hand twisted wire rope. Silver is tarnished to a warm patina. No hallmarks. Acid tested. C. 1950.