Flint stone is a hard, dark gray or black natural rock formed from microcrystalline quartz (chert). It was one of the most important materials used by early humans thousands of years ago for making tools and starting fire.
Flint stone is a hard, dark gray or black natural rock formed from microcrystalline quartz (chert). It was one of the most important materials used by early humans thousands of years ago for making tools and starting fire.
