The Bovey Formation is a deposit of sands, clays and lignite, probably over 1000 feet thick.

A smaller basin with similar deposits lies further northeast along the fault at Petrockstowe.

[3] The deposit is the result of the degradation of the neighbouring Dartmoor granite;[2] it was laid down in river flood plains and lakes during the late Eocene and Oligocene epochs.

The Bovey Formation is the major source in England for ball clay – a highly plastic fine-grained kaolinitic sedimentary clay typically used by the pottery industry.

In the past, the lignite or "Bovey Coal" was burned in local kilns; steam engines; and workmen's cottages.