Luster is resinous. Crystals are opaque. Crystal Habits include short prismatic crystals with a square cross-section and simple pyramidal terminations. Also massive, embedded irregular grains and reniform. Cleavage is poor, in two directions lengthwise, but is rarely seen.
Fracture is conchoidal.
Streak is orange to brown. Nearly always metamict and always strongly radioactive. Associated Minerals include quartz , feldspars , biotite and betafite . Best Field Indicators are color, luster, crystal habit, fracture and especially radioactivity.