The quarry was worked for Magnesian Limestone until the 1930s, when it closed. Since then a large and varied grassland has developed on the site. Magnesian limestone grassland is nationally scarce, with this site accounting for close to 8 per cent of the national total. As well as species that are characteristic of this vegetation type, there are also two orchids, fragrant orchid, Gymnadenia conopsea, and frog orchid, Coeloglossum viride, both of which are uncommon in County Durham.