Early Mexican Obsidian Warrior Ring, Size 4.75

Vintage Mexico made sterling silver ring with a obsidian warrior face cabochon. The obsidian is slightly transparent and is a dark, root beer brown color. The carved stone is set in a smooth bezel and the setting has an ornate filigree design on the shanks.  Condition: There is some noticeable surface scratching on the obsidian and natural patina on the silver.  ***All jewelry is lightly cleaned and earrings are disinfected. Personal preferences vary greatly for the amount of patina on vintage jewelry, therefore I only lightly polish with a sunshine cloth as needed. Size: The band size is 4.75 and is 1 1/8" wide at the top.  Marks: none, tests as sterling silver.  Era: 1930's to 1940's