a very fine-grained sandstone, mainly consolidated silt.
Origin of siltstone
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
a variety of fine sandstone formed from consolidated silt
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 fine-grained sedimentary rock consisting primarily of compacted and hardened silt. Siltstones are similar to shale but without laminations. They vary in color from black or gray to brown or red.
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