flint
Flint is called fossil ", mainly composed of cryptocrystalline quartz.It is relatively common siliceous rock, dense, hard, mostly gray, black, crushed with shell-like fracture, according to its existence, divided into two types: ▪ layered flint: more coexistent with phosphorus and manganese containing clay, stratified, single layer thickness is not large, but the total thickness of up to several hundred meters, there are blocks and oolitic differences ▪ tuberous flint : Prolific in limestone, spherical, ovate, rodlike, discoid, gourd-like, irregular and other tuberculosis bodies, generally only 5-15 cm, large up to 1-2 m. Flint due to hard, broken Resulting in sharp fracture, it is the earliest for the stone age of the primitive people favored, most of the stone is made of flint hit, flint and iron hit will produce sparks, so for the ancient people for fire tools, China In ancient times, a small piece of flint and a steel "fire sickle" hit the fire, so the flint is also called flint, flint gun is also the use of trigger flint trigger gunpowder. Modern use of the flint's hard nature, the flint as a research Raw materials ....