The Collaborative International Dictionary
Manganese \Man`ga*nese"\, n. [F. mangan[`e]se, 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 (melting point 1244[deg] C), but easily oxidized. Its ores occur abundantly in nature as the minerals pyrolusite, manganite, etc. Symbol Mn. Atomic number 25; Atomic weight 54.938 [C=12.011].
Note: 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 Manganese 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.
Wikipedia
Manganese(IV) oxide is the inorganic compound with the formula . This blackish or brown solid occurs naturally as the mineral pyrolusite, which is the main ore of manganese and a component of manganese nodules. The principal use for is for dry-cell batteries, such as the alkaline battery and the zinc-carbon battery. is also used as a pigment and as a precursor to other manganese compounds, such as . It is used as a reagent in organic synthesis, for example, for the oxidation of allylic alcohols. in the α polymorph can incorporate a variety of atoms (as well as water molecules) in the "tunnels" or "channels" between the magnesium oxide octahedra. There is considerable interest in as a possible cathode for lithium ion batteries.
Usage examples of "manganese dioxide".
Ayla reached for her amulet and felt for the fifth object she carried in it now: a piece of black manganese dioxide nestled in the small pouch along with the three nodules of iron pyrite stuck together, a red-stained oval of mammoth ivory, the fossil cast of a gastropod, and a chunk of red ochre.
Chunks of manganese dioxide - a colouring material later used by Cro-Magnon man - have been found in his caves, some of them worn down on one side as if used as crayons.
Down in his saboteur's treasure-house of a memory, he knew that the catalyst for hydrogen peroxide was manganese dioxide.
But she was a medicine woman, and a piece of everyone's spirit had been given to her with the piece of black manganese dioxide that she carried in her amulet.
The small lump of black manganese dioxide held a piece of the spirit of everyone in the entire Clan, not just her clan.
All the signs her totem had given to her were in it, as well as the red-stained oval from the tip of a mammoth tusk that was her hunting talisman, and the black stone, the small chunk of black manganese dioxide that held the spirit pieces of the Clan, which had been given to her when she became the medicine woman ofBrun's clan.
He learned to use and prepare mineral colours and gums -- cinnabar, manganese dioxide, calcined umber, and sticky, messy gamboge.
He knew how to produce concentrated acetic acid by the distillation of vinegar, the use of manganese dioxide in glass manufacture, and much else.