Flashing LED Circuit DIY Electronics Kit
$4.99$2.95
|
|
(L. magnes, magnet, from magnetic properties of pyrolusite; It. manganese, corrupt formof magnesia)
Recognized by Scheele, Bergman, and others as an element and isolated by Gahn in 1774by reduction of the dioxide with carbon.
Manganese minerals are widely distributed; oxides, silicates, and carbonates are themost common. The discovery of large quantities of manganese nodules on the floor of theoceans may become a source of manganese. These nodules contain about 24% manganesetogether with many other elements in lesser abundance.
Most manganese today is obtained from ores found in Russia, Brazil, Australia, Republicof S. Africa, Gabon, and India. Pyrolusite and rhodochrosite are among the most commonmanganese minerals. The metal is obtained by reduction of the oxide with Sodium, magnesium,aluminium, or by elctrolysis.
'When I examine myself and my methods of thought, I come to the conclusion
that the gift of fantasy has meant more to me than my talent for absorbing
positive knowledge.'