These lithologies often occur with subordinate amounts of pale grey silty mudstones, laminated siltstones, sandstones, conglomerate, shelly limestones and clay-ironstones.

[2] When they become exposed to the elements at the surface, the mudstones often degrade over a short period of time and weather to yellowish brown and greenish grey clays.

[5] The top of the Wadhurst Clay is marked by a distinct lithological change into the siltstones of the Tunbridge Wells Sand Formation.

Instability, resulting in landslips, often occurs along shear surfaces and weaknesses that originally developed during the Late Devensian glaciation.

Landslips often occur at or close to the upper boundary of the Wadhurst Clay, which is shared with the overlying Tunbridge Wells Sand Formation.