Augite is a single chain inosilicate mineral, (Ca,Na)(Mg,Fe,Al)(Si,Al)2O6. The crystals are monoclinic and prismatic. Augite has two prominent cleavages, meeting at angles near 90 degrees.
Characteristics[edit | edit source]
It is found in igneous rocks, it also occurs in relatively high-temperature metamorphic rocks.Occasional specimens have a shiny appearance that give rise to the mineral's name, which is from the Greek augites, meaning "brightness", although ordinary specimens have a dull (dark green, brown or black) finish.