Category:Pyrolusite

Pyr`o*lu"site, n. Etym: [pyro- + gr. (min.)

Defn: manganese dioxide, a mineral of an iron-black or dark steel- Gray color and metallic luster, usually soft. Pyrolusite parts with Its oxygen at a red heat, and is extensively used in discharging the Brown and green tints of glass (whence its name).