Graphite

Graphite is a hexagonally crystallised form of pure carbon. Its smooth, parallel crystalline layers lie in weakly bonded but solid basal planes. Graphite is extremely anisotropic, especially with regard to hardness and electrical conductivity.

It is a commonly occurring natural mineral, but for industrial applications it is produced synthetically. This is done by coking petroleum, coal or plastics, which initially produces amorphous, graphitisable carbons. Graphitisation takes place at around 3,000 °C and in the absence of air.