- a granular igneous rock consisting essentially of plagioclase feldspar and hornblende.
Origin of diorite
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Examples from the Web for diorite
Quartz porphyry, diabase and diorite appear in the Ardennes.
A diorite block, found at Susa in 1902, has the law engraved on it.The Lords of the Ghostland
Diorite is a crystalline aggregate of a soda-felspar and hornblende.
What is the mineralogical composition of syenite and diorite?
They are in diorite, and have the name of Apepi engraved upon them.Ancient Egypt
- a dark coarse-grained igneous plutonic rock consisting of plagioclase feldspar and ferromagnesian minerals such as hornblende
C19: from French, from Greek diorizein to distinguish (from dia- apart + horizein to define) + -ite 1
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
- A gray, coarse-grained plutonic rock. Diorite consists mainly of sodium-rich plagioclase and one or more mafic minerals such as biotite, hornblende, or pyroxene. It is the coarse-grained equivalent of andesite.
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