Vintage Navajo sterling silver ring from the Fred Harvey era. It is tarnished black and does has stamping including arrows on the sides. The stone is very dark, almost black turquoise stone. It will polish up, I decided to leave it in original patina. Crusty old silver polish up inside the back. Size 6.5  Measure 1 /2" in diameter. Weight: 3 grams. No hallmarks.