Back in 1996, when undertaking geological surveys for the South Yorkshire RIGS Group, I encountered an old quarry face below the level of Greenlands Park, but the area has since been developed and access is now only available with the permission of the various landowners.
On the occasion of my walk from St. John's church in Throapham to South Anston in late May 2021, I didn’t go and have another look, but when exploring the area around the housing estate after a visit to Anston Stones Wood in 2014, I got talking to a houseowner on Limekilns who invited me to have a look at the 50 metres long old quarry face in his back garden.
The northern part of the garden had been landscaped with blocks of limestone and planting had obscured much of the rock face. In the southern part, although it was still full of builder’s plant associated with the new house that was just being completed, a good section of massive limestone, with beds at least 50 cm thick, could be clearly seen.
The long history of extensive repair to the fabric of the Palace of Westminster has been the source of considerable debate, with a lack of supervision and quality control at the quarry and unfamiliarity with Anston stone by the London stonemasons often being cited as reasons for its failure.
I only spent 10 minutes having a quick look at the old quarry face – where drill holes for plug and feathers are preserved - and taking a set of record photographs, without closely studying the physical characteristics of the stone; however, it was enough to see that even in the most massive beds, there are patterns of fracture that would be considered undesirable in a building stone.
In plain ashlar masonry, as seen in the keep of Conisbrough Castle and at Brodsworth Hall, this is unlikely to have a great effect on its durability; however, elaborately ornamented Gothic Revival style detailing greatly increases the surface area exposed to the elements – which includes any natural defects within the stone.
A lower level exposure with fracturing in the rock face |
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