East of Bolsover, the Coal Measures are covered uncomformably by the Permian breccias and magnesian limestone.
East of Bolsover, the Coal Measures are covered unconformably by the Permian breccias and magnesian limestone.
The material is magnesian limestone.
The material used is a soft, porous magnesian limestone, which is well adapted to the purpose in view.
Ore endowed with this curious property was well known to the ancient Greeks and Romans, who, because it occurred plentifully in the district of Magnesia near the Aegean coast, gave it the name of magnes, or the Magnesian stone.