[1] The name distinguishes it from the Old Red Sandstone which is largely Devonian in age, and with which it was originally confused due to their similar composition.

The sandstone also underlies parts of Lancashire and Cumbria, and east of the Pennines it extends through Nottinghamshire and central Yorkshire.

[1] The sandstone units are monomineralic, consisting only of quartz grains (negligible amounts of other minerals may be present), and they are cemented together with the ferric iron oxide haematite (Fe2O3).

The presence of this particular iron oxide is evidence for a terrestrial environment of deposition such as a desert, and gives the rocks the red colour which they are named after.

[2] An earliest Permian (Asselian) fauna is known from the Kenilworth Sandstone Formation of the English Midlands, including primitive synapsids and temnospondyl amphibians.