Bronzite

Rather than a distinct species, it is really a ferriferous variety of enstatite, which owing to partial alteration has acquired a bronze-like sub-metallic luster on the cleavage surfaces.

[2] The ferriferous varieties are liable to a particular kind of alteration, known as schillerization, which results in the separation of the iron as very fine films of oxide and hydroxides along the cleavage cracks of the mineral.

[2] Like enstatite, bronzite is a constituent of many mafic to ultramafic igneous rocks, such as, norite, gabbro, and especially peridotite, and of the serpentinites which have been derived from them.

[3] Bronzite is sometimes cut and polished, usually in convex forms, for small ornamental objects, but its use for this purpose is less extensive than that of hypersthene[citation needed].

Masses sufficiently large for cutting are found in the norite of the Kupferberg in the Fichtel Mountains, and in the serpentine of Kraubat near Leoben in Styria.