Imported Permian Limestone
Magnesian limestone of Permian age (290-245 million years old) has been quarried in England since Roman times and is still actively quarried for aggregate and building stone. A long narrow outcrop around 300km long and 8 wide stretches from South Shields to Nottingham extending into a 600km2 plateau at its end in County Durham.
It has been quarried throughout the extent of the outcrop but particularly in the Mansfield and Tadcaster areas. Durability and quality of stone varies depending on the source, a poorer variety was infamously used to build the Houses of Parliament, London of which around 50% has been replaced due to poor performance. Magnesian limestone is generally white to yellow in colour .