Colour and mosaics

Common colours used and their sources

White: hard chalk, oolitic limestone, carboniferous limestone

Reds, orange: chopped brick and tile, and samian vessels, old red sandstone, Purbeck marble

Blues: lias limestone, shale, Purbeck marble

Black, grey: shale, burnt brick and tiles

Pink: chalk, sometimes burnt

Purple: Pennant sandstone

Green: lower greensand, Purbeck marble

Brown: argillaceous limestone, ironstone