What is "bustamite"

n. (context mineral English) A triclinic-pinacoidal mineral containing calcium, manganese, oxygen, and silicon.

Bustamite is a calcium manganese inosilicate (chain silicate) and a member of the wollastonite group. Magnesium, zinc and iron are common impurities substituting for manganese. Bustamite is the high-temperature polymorph of CaMnSiO and johannsenite is the low temperature polymorph. The inversion takes place at , but may be very slow.
Bustamite could be confused with light-colored rhodonite or pyroxmangite, but both these minerals are biaxial whereas bustamite is biaxial .