It is a soft and flexible mineral, with low hardness, between 1 and 2 in Mohs scale, and it can be scratched by one´s nail. Graphite is usually refractory, it is the best thermal and electrical conductor among non-metals, and it is also chemically inert.
Natural graphite is widely distributed in nature in igneous, sedimentary, metamorphic rocks, and iron-nickel meteorites.
Graphite main use is in traditional refractory industry, in high temperature bricks and coatings used in metal, ceramic and petrochemical manufacturing, and cement industries. Apart from these markets, graphite is used in pencils (usually mixed with kaolinite), in electrodes, polishing brushes, lubricants, reactors, crucibles, batteries, in iron and steel industry, in paints, electroplating and ammunition.
Source: MM Gerdau - Museu das Minas e do Metal -