schefferite
noun
schef·fer·ite
ˈshefəˌrīt
plural -s
: a mineral (Ca,Mn)(Mg,Fe,Mn)Si2O6 that is a brown to black variety of pyroxene containing manganese and frequently much iron
Word History
Etymology
Swedish schefferit, from H. T. Scheffer †1759 Swedish chemist + Swedish -it -ite