Students from MLA1 spent the day learning how 310 million year old sandstone is converted from rock face to paving. Marshalls' own the quarry at Scoutmoor and it is their primary production facility for York stone, which is utilised as the principle paving product in most major cities in England, lasting up to 100 years.
Paul Thwaites from Marshalls explained to students how the rock was removed from the quarry face in up to 15 ton pieces and how the overburden of less durable rock, sands and shales are recycled as aggregates. The only material not used is a thin seam of coal, which is of too poor quality. Large pieces of rock, removed from the face, are split across bedding planes, through the traditional method of plug and feather or drilled to take an explosive charge.
Although quarrying is a destructive process, two Peregrine falcons have taken up residence on the old quarry face. Their nest is protected by CCTV cameras installed by Marshalls, to deter poachers taking the young for sale in the Middle East.