Mexican Crystal Opal Ring in Sterling Silver Size 6

Sterling silver ring made in Mexico. It is set with a Mexican crystal opal that has play of color in the sun. Play of color is not strong, but it is present with purple and green being the strongest flash. 

Size 6 Face measures 16.7 mm by 10.8 mm. Marked sterling inside. Tarnished. 

The stone has some interior crazing near the base of the cabochon which is common for these stones.