"Coal."@en . "Gwscwm Coal (South Wales)"@en . . . . "stable"@en . . "Coal. Stratified bedrock. Occurs onshore. Deposited during the Bolsovian Substage (Carboniferous Period) (314.75-310 Ma BP)."@en . "Gwscwm Coal (South Wales)"@en . . "314.75"^^ . . . "GCCO"@en . "310.0"^^ . .