Halecombe Quarry – Grid Reference ST697474, is situated near the village of Leigh on Mendip. Though there is evidence of quarrying since the Roman times, quarrying started in earnest at the time of WWII. The quarry was purchased by Hobbs in the 1960s and subsequently worked by Wimpey Hobbs following their amalgamation in the 1980s. It is has been worked by Lafarge Tarmac since 1996. The rock represents nearly a full sequence through the Carboniferous Limestone group, some 350 – 320 million years old. It dips sub vertically and steeply northwards, becoming younger as you move north through the sequence. Near vertical fissures and joints with calcite mineralisation are evident and tufa growth around ground water seepages. Abundant shelly fossils and corals occur. The steeply dipping nature of the limestone means it can be quarried to great depths, without spreading out across the landscape.
Historical Notes: www.lafargetarmac.com/halecombe-quarry/geology/