Flint is a sedimentary cryptocrystalline form of the mineral quartz. It is classified as a variety of chert and occurs as nodules or masses in sedimentary rocks, such as chalks and limestone.
Flint has been historically used in the making of stone tools as it is a hard material which breaks into sharp edges. It was one of the primary materials used to define the stone age. Later it was mined by Native Americans and traded across the eastern United States.
Flint has also been used to in guns and for the starting of fires as it produces a spark when struck against steel.