"CWCO"@en . . . "stable"@en . "318.0"^^ . "Crow Coal (Durham)"@en . . . "Coal. Stratified bedrock. Occurs onshore. Deposited during the Duckmantian Substage (Carboniferous Period) (318-314.75 Ma BP)."@en . . "314.75"^^ . . "Coal."@en . . . "Crow Coal (Durham)"@en .