- a granular igneous rock consisting chiefly of orthoclase and oligoclase with hornblende, biotite, or augite.
Origin of syenite
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for syenite
The complete gradation from syenite to bauxite has been shown.The Economic Aspect of Geology
C. K. Leith
They sought no quarried blocks of syenite or granite for their work.
The Syenite granite was very hard, and capable of taking a high polish.
Of those standing, twenty-seven are made of Syenite granite.
In syenite and greenstone it occurs more commonly than orthoclase.Geology
- a light-coloured coarse-grained plutonic igneous rock consisting of feldspars with hornblende or biotite
C18: from French syénite, from Latin syēnītēs lapis stone from Syene (Aswan), where it was originally quarried
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 light-colored, coarse-grained igneous rock consisting primarily of alkali feldspar together with some mafic minerals, especially hornblende. Unlike most igneous rocks, syenite has little or no quartz. It is believed to form from the cooling of magma that forms at very high temperatures and at great depths. It is the coarse-grained equivalent of trachyte.
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