Sandstone
The catacombs, like many of
the buildings in the cemetery, are built of local sandstone.
Many of the blocks are badly weathered and some are even
weaker than the mortar that holds them together.
The weathering shows how this sedimentary stone was created.
The sand in ancient rivers was deposited in layers that then
solidified to give the cross-bedding that you can see here.
The rusty brown lumps in the sandstone are ironstone
nodules. It is because of this local ironstone that Sheffield
became a centre for steel production.
Detail of the weathered
sandstone catacombs showing the cross-bedding. |
