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The Epic Interactive Encyclopedia 1998
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Epic Interactive Encyclopedia, The - 1998 Edition (1998)(Epic Marketing).iso
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Manganese
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1992-09-03
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A hard, brittle, grey-white metallic element,
symbol Mn, atomic number 25, atomic weight
54.9380. It resembles iron (and rusts), but
it is not magnetic and is softer. It is used
chiefly in making steel alloys, also alloys
with aluminium and copper. It is used in
fertilizers, paints, and industrial
chemicals. It is a necessary trace element in
human nutrition. The name is old, deriving
from the French and Italian forms of Latin
for magnesia (MgO), the white tasteless
powder used as an antacid from ancient times.
manganese ore
Any mineral from which manganese is produced.
The main ores are the oxides, such as
pyrolusite, MnO2; hausmannite, Mn3O4; and
manganite, MnO(OH). Manganese ores may
accumulate in metamorphic rocks or as
sedimentary deposits, frequently forming
nodules on the sea floor (since the 1970s
many schemes have been put forward to harvest
deep-sea manganese nodules). The world's main
producers are the USSR, South Africa, Brazil,
Gabon, and India.