- a granular sedimentary rock composed of quartz and feldspar or mica; a feldspathic sandstone.
Origin of arkose
Borrowed into English from French around 1830–40
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for arkose
At the base there is often an arkose, composed largely of fragments of serpentine and granite derived from the ancient floor.
The lowest cretaceous rocks yet found are composed of an arkose, derived in large part from the original igneous mass.The History of Cuba, vol. 1
Willis Fletcher Johnson
- a sandstone consisting of grains of feldspar and quartz cemented by a mixture of quartz and clay minerals
C19: from French
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 usually pinkish or red sandstone consisting primarily of quartz and feldspar. Arkose usually forms as the result of the rapid disintegration of granite in areas of vigorous erosion. Its grains are usually angular and poorly sorted (mixed randomly in differing sizes).
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