. . "ENVO"^^ . "Wikipedia:Shale"^^ . "shale"^^ . "ENVO:00002056"^^ . "A fine-grained sedimentary rock whose original constituents were clays or muds. It is characterized by thin laminae breaking with an irregular curving fracture, often splintery and usually parallel to the often-indistinguishable bedding plane."^^ .