It is found in igneous and some metamorphic rocks as well as in stony and iron meteorites. It forms a solid solution series with the minerals enstatite and ferrosilite, being a mid-way member between the two.
Pure enstatite contains no iron, while pure ferrosilite contains no magnesium; hypersthene is the name given to the mineral when a significant amount of both elements are present. Distinctly developed crystals are rare, the mineral being usually found as foliated masses embedded in the igneous rocks norite and hypersthene-andesite, of which it forms an essential constituent. The coarse-grained labradorite-hypersthene-rock (norite) of the island of Paul off the coast of Labrador has furnished the most typical material; and for this reason the mineral has been known as Labrador hornblende or paulite.