Mines and Minerals in the Tucson Mountains - Arizona-Sonora Desert Museum
The most famous mine in this area is the Old Yuma Mine, which originally opened in 1885. Along with galena, the dominant ore-bearing lead mineral, caches of beautiful vanadinite and wulfenite crystals were found in pockets carved by earlier corrosive fluids. The colors of vanadinite are striking, ranging from fiery red to brick red or yellow.