Origin of clay stone
First recorded in 1770–80
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Science definitions for claystones
[ klā′stōn′ ]
A fine-grained, dark gray to pink sedimentary rock consisting primarily of compacted and hardened clay. Claystone is similar to shale but without laminations.
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