Pyrophyllite seems to be best as a carrier for insecticides and is often the filler for these products. Although an ordinary metamorphic mineral in most regards, pyrophyllite is still quite interesting and does form some very attractive mineral specimens. The radiating stellate aggregates that come from Mariposa County, California and North Carolina for example are quite appealing with their bright pearly luster and radiating habit. It can also be stained brown by iron oxides. Luster is greasy to dull, but pearly on cleavage surfaces.
Crystals are mostly translucent to opaque.
Crystal Habits include the typical fine grained, fibrous and lamellar masses, stellate aggregates and radiating spherules. Individual crystals are rare, but usually have a tabular subhedral or distorted form. Cleavage is perfect in one direction. Fracture is uneven or splintery. Streak is white.