langbanite
noun
lang·ban·ite
| \ ˈlȯŋbəˌnīt\
plural -s
Definition of langbanite
: a hexagonal mineral (Mn,Sb,Ca,Fe,Mg)O8(SiO4)(?) occurring in iron-black prismatic crystals consisting of a manganese, iron, and antimony silicate and oxide (hardness 6.5; specific gravity 4.92)
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