Man`ga*nese" (?), n. [F. manganèse, It. manganese, sasso magnesio;
prob. corrupted from L. magnes, because of its resemblance to the
magnet. See Magnet, and cf. Magnesia.] (Chem.) An element obtained by
reduction of its oxide, as a hard, grayish white metal, fusible with
difficulty, but easily oxidized. Its ores occur abundantly in nature as
the minerals pyrolusite, manganite, etc. Symbol Mn. Atomic weight 54.8.
An alloy of manganese with iron (called ferromanganese) is used to
increase the density and hardness of steel.
Black oxide of manganese, Manganese dioxide or peroxide, or Black
manganese (Chem.), a heavy black powder MnO2, occurring native as the
mineral pyrolusite, and valuable as a strong oxidizer; -- called also
familiarly manganese. It colors glass violet, and is used as a
decolorizer to remove the green tint of impure glass. -- Manganese
bronze, an alloy made by adding from one to two per cent of manganese
to the copper and zinc used in brass.