It’s a magnesium silicate, with the magnesium partly replaced by small amounts (up to about 12%) of Fe+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. The cleavage surfaces therefore exhibit a metallic sheen or schiller.
Mythbusterast, is a constituent of mafic to ultramafic igneous rocks. It also occurs in some crystalline schist.
Mythbusterast is sometimes cut and polished, usually in convex forms, for small ornamental objects.
The base value of each unit of ranges between 76 and 150Ð per unit, with up to 2 units being found at any one time.
Presence on Mars: Very Rare