Upper Triassic – White Lias Limestones   Lead author: Geoff Townson

Immediately below the Blue Lias Formation is the youngest of the Triassic building stones, informally known as the “White Lias”. This geological formation consists of several layers of very hard, cream-coloured, fine-grained limestone.  A thickness of at least 6m is exposed at Pinhay Bay west of Lyme Regis.  The White Lias was deposited in a very shallow sea, probably slightly high salinity, about 202 million years ago. 

White Lias kerb in Pound Street, Lyme Regis. Photo: GT.

The White Lias was quarried inland, along with the overlying Blue Lias, at nearby Uplyme (just in Devon), to 1920.  In Lyme Regis, Pound Street has a long run of White Lias kerbs on its northern side.  It is seen in many walls in the area and probably many old buildings yet to be described.  Some of the layers produced were thin-bedded flagstones with small fossils (bivalves & gastropods) and ripple marks.  It is still worked in south Somerset (Langport area) and is widely used as a building stone and flooring in the region.

See also:
Industrial Lyme: Paper 5 - Stone quarrying
Fowler, Harris, Osborn & England, Haycraft, Harvey, Porter, Hutchinson &
Frean, Walker, Gollop, Shore, Philpot, Spoor and others.
© Richard Bull & Lyme Regis Museum 2010 Revised April 2015
WGT Jan 2017