This is a marvelous 1960s Navajo convex silver pin having a large cluster of Old red Mountain turquoise stones surrounded by handcarved silver rope and a handcarved silver scalloped border accented with handcarved silver beads! The pin measures around 2″? X 2″ΒΌ. No marks but tested as sterling silver great addition to your collection?? A. Brief History on Red Mountain Turquoise. The Red Mountain Turquoise Mine is located in Lander County, Nevada. This mine has produced a large quantity of graded natural Turquoise and the best Red Mountain Turquoise rivals some of the high quality Turquoise produced by the best mines in the Southwest. Red Mountain Turquoise with its intricate often red spider web matrix is usually cut into Red Mountain Spiderweb Turquoise Cabochons and set in the finest gold and silver American Indian jewelry. The spider web Turquoise from the Red Mountain Turquoise mine is some of the finest, only compared with the likes of Blue Wind, Number Eight, Lone Mountain, Darling Darlene, Indian Mountain and Lander Blue. This stone has been used in many fine Turquoise Jewelry. Pieces both gold and silver by many famous artists.