gritstone
/ˈɡrɪtˌstoʊn/
noun
- A hard, coarse-grained sandstone used for building and sharpening tools.
- Gritstone is often found in the hills of northern England and is popular for making grindstones.
- He used a piece of gritstone to sharpen the blade of his axe.
- The old mill was built from local gritstone that had a rough, sandy texture.