What is etym: [G. shale.] (Geol.) A fine-grained sedimentary rock of a thin, laminated, and often friable, structure. Bituminous shale. See under Bituminous called?

shale — Etym: [G. shale.] (Geol.) A fine-grained sedimentary rock of a thin, laminated, and often friable, structure. Bituminous shale. See under Bituminous. (Webster's 1913.)

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