Guided walk: history of fuller’s earth workings around Woburn Sands

Saturday 15th May 2021 14:00 - 17:00

Within the local Woburn Sands Formation of the Lower Greensand (Early Cretaceous age, ~113 million years old), which forms the Greensand Escarpment overlooking Milton Keynes to the north, are discrete layers of a pale clay known as ‘fuller’s earth’. It accumulated as weathered volcanic ash that became ponded in depressions within shallow marine sand deposits.

Because of its special absorptive properties, this clay was used historically for ‘fulling’ (de-greasing) wool and hence was of considerable importance in the medieval economy of England. More recently it has been used as a bonding agent for foundry sands and for drilling-mud, cat-litter, cosmetics, etc. In the local area it has been excavated since at least the 13th C (and possibly in Roman times) – initially by digging at outcrop, but later by sub-surface mining in the 19th C and then from opencast pits in the 20th C. Historical documentary records of such extraction are good from the late 19th C, but are much more limited for the earlier, smaller-scale workings, some of which appear only as stylised ‘pitts’ shown in old maps. For the majority of older workings local minor topographical features are the only remaining evidence.

The trail focuses on such remaining topographical clues, both for the older workings and the more recent back-filled opencast pits, emphasizing the idea of ‘reading the landscape’ in order to understand the historical relationship between geology and human activity.