Limestone of high quality lies near the surface at Rushall. It was exploited by the Romans and through the Middle Ages for building and agricultural purposes. The use of limestone as flux for smelting iron caused great expansion in mining during the Industrial Revolution. A new settlement grew up at Daw End, and the Hay Head and Linley workings were both on a large scale. The quarries in Rushall Hall's park flooded to become the Park Lime Pits - today a nature reserve. The Arboretum lakes, then also in Rushall, were similarly formed by quarrying.