PYROCHROITE

ˌpīrəˈkrōˌīt, pīˈräkrəˌwīt noun

( -s )

Etymology: Swedish pyrochroit, from pyr- + Greek chrōs color + Swedish -it -ite; from the fact that it becomes colored when heated — more at chromatic

: a mineral Mn(OH) 2 that is a natural manganous hydroxide