. "Coal."@en . "321.5"^^ . . . "Ashover Coal"@en . . "Ashover Coal"@en . . "320.0"^^ . "Coal. Stratified bedrock. Occurs onshore. Deposited during the Marsdenian Substage (Carboniferous Period) (321.5-320 Ma BP)."@en . "stable"@en . . . "ASHCO"@en . .