Gritstone is a sedimentary rock composed of coarse sand grains and is a coarser version of sandstone.

Gritstone is usually laid down in water and frequently shows signs of cross bedding or current bedding.

It is quarried for building material. British gritstone was used for millstones to mill flour and sharpen blades, giving rise to its other common name of millstone grit.

See also

• List of minerals
• List of stone