This specimen contains yellow-orange wulfenite crystals that formed in associaiton with mimetite. This specimen was collected from the San Francisco Mine in Sonora, Mexico.
is a lead based, molybdate mineral with a chemical formula Pb(MoO4). It forms as a secondary mineral in the oxidation zones of hydrothermal lead deposits, with coloring ranging anywhere between yellow to bright orange and red, and occasionally brown. Typically forming as tabular, stubby or pyramidal crystals, this unique mineral can be both brilliantly transparent and opaque.
While these crystals are safe to hold, due to their being lead based, washing your hands following handling is strongly suggested.
Mimetite is a lead chloro-arsenate mineral with the chemical formula of Pb5(AsO4)3Cl. Depending on conditions, during formation/replacement, arsenate radicals (As04) can be replaced by a phosphate (PO4) or vanadate (VO4) radical. This alteration is what leads to the formation of pyromorphite and vanadinite, hence why they're typically found associated with each other. Regularly ranging between red and yellow in color, mimetite can occur in a variety of structures, from small prismatic clusters and crusts, to incredible hexagonal crystals both thick and thin.