. . "BYCH"@en . "318.0"^^ . "Coal. Stratified bedrock. Occurs onshore. Deposited during the Langsettian Substage (Carboniferous Period) (319-318 Ma BP)."@en . . . "stable"@en . . "319.0"^^ . . "Bychton Two Yard Coal (North Wales)"@en . . "Bychton Two Yard Coal (North Wales)"@en . "Coal."@en .