It is a member of the autunite group. These include carnotite, tyuyamunite, torbernite and autunite. Torbernite is isostructural with the related uranium mineral, autunite. Autunite was discovered in 1852 near Autun, France, which is also autunite's namesake. Specimens of the rare uranium minerals, such as uranophane, torbernite, and autunite, have been found. Some uranophane and autunite are also present. The uranium mineral autunite is found in the country rock surrounding the dome. Uranium occurs as uraninite and autunite in shear zones in granodiorite. The veins contain pitchblende, autunite and uranophane, with accessory marcasite and barite. The uranium is contained in autunite, uraninite, and coffinite, with gangue minerals pyrite and marcasite. Autunite fluoresces bright green to lime green under UV light. Autunite is also found in Cornwall, Saxony, and North and South Dakota. Autunite was named after the town of Autun, France, where the mineral was initially found.