1) Grit 2) Gritrock 3) Sandstone 4) Sedimentary rock 1) Grit 2) Gritrock 
Gritstone or grit is a hard, coarse-grained, siliceous sandstone. This term is especially applied to such sandstones that are quarried for building material. British gritstone was used for millstones to mill flour, to grind wood into pulp for paper and for grindstones to sharpen blades. `Grit` is often applied to sandstones composed of angular s.....
• (n.) See Grit, n., 4.
A sandstone, with coarse and usually angular grains.
A coarse-grained sandstone.