- any of a group of granular igneous rocks having approximately equal amounts of orthoclase and plagioclase feldspar, intermediate in composition between syenite and diorite.
Origin of monzonite
1880–85; < German Monzonit, named after Monzoni, mountain in Tyrol; see -ite1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- a coarse-grained plutonic igneous rock consisting of equal amounts of plagioclase and orthoclase feldspar, with ferromagnesian minerals
C19: from German, named after Monzoni, Tyrolean mountain where it was found
- An igneous rock composed chiefly of plagioclase and orthoclase, with small amounts of amphibole, pyroxene, and biotite. Monzonite contains little or no quartz.
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