siltstone definition by American Heritage Dictionary
The American Heritage® Dictionary of the English Language, 4th edition Copyright © 2010 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
A fine-grained rock of consolidated silt.
siltstone - Science Definition
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.