Late 19th century; earliest use found in Edward Dana (1849–1935), mineralogist and physicist. From Swedish manganosit from mangano- + -sit, probably after mineral names comprising a first element ending in -s + -ite, as German Epidosit epidosite, Globosit globosite, Kyrosit kyrosite: -s- occurs by a similar process of analogy in Spanish morenosita.