Graphite

One of the allotropes of carbon. Unlike diamond, graphite is a conductor, and can be used, for instance, as the material in the electrodes of an electrical arc lamp.

The pi orbital electrons delocalized across the hexagonal atomic sheets of carbon contribute the graphite's conductivity. In an oriented piece of graphite, conductivity parallel to these sheets is greater than that perpenicular to these sheets.

The loose coupling among the sheets in graphite contributes to another industrially-important property--graphite powder is used as a dry lubricant.