Most distinguishing features:Colour, cleavage and hardness are indicative of a pyroxene. Augite has 2 cleavage planes at 90°.
Industrial/economical uses:None.
Most distinguishing features:Resembles tremolite, but has different cleavage.
Industrial/economical uses:Replacement for chrysotile asbestos in fire-resistant building supplies. Also used in paints, film and plastics.