"Coal. Stratified bedrock. Occurs onshore. Deposited during the Asbian Substage (Carboniferous Period) (337-330.9 Ma BP)."@en . "Coal."@en . "stable"@en . . "Diamond Coal (Northumberland)"@en . . "330.9"^^ . "Diamond Coal (Northumberland)"@en . "337.0"^^ . . . . . . "DIMND"@en .