It is said to fluoresce with a brightness comparable to some of the brightest fluorescing minerals in the world. The uranium is the fluorescent activator in meta-autunite and autunite. Trace amounts of uranium are responsible for the green fluorescence in opal and adamite as well. Remember because of the uranium, meta-autunite is a radioactive mineral and should be stored away from other minerals that are affected by radioactivity and human exposure should always be limited. Luster is vitreous or pearly to dull.
Crystals are translucent to opaque.
Crystal Habits include tabular square crystals dominated by two pinacoid faces. Also as crusts, micaceous, foliated and earthy. Many crystals are pseudomorphs of autunite . Cleavage is perfect in one direction. Fracture is uneven.