manganite

A steel-gray to black mineral, MnO(OH), found in North America and Europe; manganese oxide.

A hydrated oxid of manganese occurring in orthorhombic crystals of a steel-gray or iron-black color and brilliant luster, also in masses having a columnar structure. It is often altered, by loss of water, to pyrolusite. Also called gray manganese ore.

A substance which may be viewed as a compound of manganese dioxid with the monoxid of a more basic or electropositive metal.

One of the oxides of manganese; — called also gray manganese ore. It occurs in brilliant steel-gray or iron-black crystals, also massive.

A compound of manganese dioxide with a metallic oxide; so called as though derived from the hypothetical manganous acid.

a dark gray mineral of manganese, MnO(OH), found throughout North America and Europe

a black mineral consisting of basic manganese oxide; a source of manganese