水锰矿
Manganite \Man"ga*nite\, n.
1. (Min.) One of the oxides of manganese; -- called also
{gray manganese ore}. It occurs in brilliant steel-gray or
iron-black crystals, also massive.
2. (Chem.) A compound of manganese dioxide with a metallic
oxide; so called as though derived from the hypothetical
manganous acid.
manganite
n : a black mineral consisting of basic manganese oxide; a
source of manganese