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 (do͞o′nīt′, dŭn′īt′)
A dense igneous rock that consists mainly of olivine and is a source of magnesium.

[After Mount Dun in northern South Island, New Zealand.]

du·nit′ic (do͞o-nĭt′īk, də-) 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.


relating to dunite
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
References in periodicals archive ?
The population is represented mainly by lherzolitic-harzburgitic (dunitic) compositions, mostly with a 0.55-0.63 range of (Si[O.sub.2] + [Al.sub.2][O.sub.3])/(MgO + Fe[O.sub.t]) molar ratio.
They occur in dunitic peridotite of the Chukotat group, 'sandwiched' between gabbros of the Watts and Povungnituk groups.
The veiny orebodies are irregular in form and structure, with much faulting and folding, although a feature common to all of them is their sharp cut-off from the surrounding dunitic rocks.