Upper Carboniferous. Millstone Grit – Yorkshire and Derbyshire Posted on 6 March 202324 July 2024 By Elizabeth Laycock No Comments on Upper Carboniferous. Millstone Grit – Yorkshire and Derbyshire E9E10F1 F2F3F4 F5F6F7 F8F9F10 G1G2G3 G4G5H1 H2H5H6 H7H8H9 H10 Carboniferous, Sandstone, Sedimentary Tags:Derbyshire Atlas, Greater Manchester Building Stone Atlas, Lancashire Building Stone Atlas, Merseyside Building Stone Atlas, North and East Yorkshire Atlas, West and South Yorkshire Atlas