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[uhl-truh-maf-ik] /ˌʌl trəˈmæf ɪk/
adjective, Geology
Origin of ultramafic
1940-45; ultra- + mafic Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for ultramafic
  • ultramafic magmas produce sulfide ore with higher nickel-copper ratios than mafic magmas.
  • Typically, a layered mafic-ultramafic intrusion consists of two main sections: an ultramafic series and a mafic series.
  • The chemical composition of igneous rock can be broken into four main types: felsic, intermediate, mafic and ultramafic.
ultramafic in Science
Containing mainly mafic minerals. Used of igneous rocks and often used interchangeably with ultrabasic. Dunite is an ultramafic rock.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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