It can be beautifully colored although often too dark, appearing black. It has a nice high luster due to its lead content. It is often associated with other rare secondary minerals that are found in the oxidation zone of ore deposits. These minerals are all trigonal, contain a sulfate ion group and have six hydroxides. Luster is vitreous, adamantine to greasy.
Specimens are transparent to translucent.
Fracture is conchoidal. Hardness is 4. Streak is greenish yellow. Associated Minerals include mimetite , jarosite , conichalcite , anglesite , galena , sphalerite , arsenopyrite , pyrite , pyrrhotite , descloizite , aegirine , hemimorphite , microcline , muscovite , arthurite , tetranatrolite and natrolite . Best Field Indicators are crystal habit, density, color, streak, luster and hardness.