Graphite is a crystalline form of the element carbon. It consists of stacked layers of graphene. Graphite occurs naturally and is the most stable form of carbon under standard conditions. Synthetic and natural graphite are consumed on a large scale for uses in pencils, lubricants, and electrodes. Under high pressures and temperatures it converts to diamond. It is a good conductor of both heat and electricity.
Graphite specimen
Scanning tunneling microscope image of graphite surface
Graphite plates and sheets, 10–15 cm high; mineral specimen from Kimmirut, Canada
Graphited Wood Grease 1908 ad in the Electric Railway Review
Carbon is a chemical element; it has symbol C and atomic number 6. It is nonmetallic and tetravalent—meaning that its atoms are able to form up to four covalent bonds due to its valence shell exhibiting 4 electrons. It belongs to group 14 of the periodic table. Carbon makes up about 0.025 percent of Earth's crust. Three isotopes occur naturally, 12C and 13C being stable, while 14C is a radionuclide, decaying with a half-life of about 5,730 years. Carbon is one of the few elements known since antiquity.
Graphite (left) and diamond (right), two allotropes of carbon
A large sample of glassy carbon
Comet C/2014 Q2 (Lovejoy) surrounded by glowing carbon vapor
Graphite ore, shown with a penny for scale