"Brass Vein Coal (South Wales)"@en . "298.9"^^ . . "Coal."@en . "359.3"^^ . . . . . "Brass Vein Coal (South Wales)"@en . . "Coal. Stratified bedrock. Occurs onshore. Deposited during the Carboniferous Period (359.3-298.9 Ma BP)."@en . "stable"@en . "BRVC"@en . .