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 (măng′gə-nēz′, -nēs′)
n. Symbol Mn
A gray-white brittle metallic element, occurring in several allotropic forms, found worldwide, especially in the ores pyrolusite and rhodochrosite and in nodules on the ocean floor. It is alloyed with steel to increase strength, hardness, wear resistance, and other properties and with other metals to form highly ferromagnetic materials. Atomic number 25; atomic weight 54.938; melting point 1,246°C; boiling point 2,061°C; specific gravity 7.21 to 7.44; valence 1, 2, 3, 4, 5, 6, 7. See Periodic Table.

[French manganèse, from Italian manganese, from Medieval Latin magnēsia, mineral ingredient of the philosophers' stone; see magnesia.]

man′ga·ne′sian (-nē′zhən, -shən) adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
References in periodicals archive ?
The lower deposit, below the 1 m thick organic sands with the Neolithic, had 7 bone beds, where the preservation is excellent, though there is some evidence of manganesian deposition on the surface of some bones.