a fine-grained igneous rock having such compact texture that the constituent minerals cannot be detected with the naked eye.
Origin of aphanite
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
any fine-grained rock, such as a basalt, containing minerals that cannot be distinguished with the naked eye
Word Origin for aphanite
C19: from Greek aphanēs invisible
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
Of or relating to an igneous rock in which the crystals are so fine that individual minerals cannot be distinguished with the naked eye. Aphanitic rocks are extrusive rocks that cooled so quickly that crystal growth was inhibited. Compare phaneritic.
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