Bishop’s Frome Limestone
A calcrete, formed within the soil horizon during the Devonian, this rubbly limestone occurs at the boundary between the Raglan Mudstone and St Maughans Sandstone and is not widely used for building. Some use is made in Bishop’s Frome but generally it has been exploited for lime-burning. It also forms an important source for tufa due the impermeable mudstones beneath generating lines of spring rich in dissolved calcium carbonate which precipitate limestones over mossy falls.