Deposited by chemical vapor decomposition of hydrocarbon gases above 1,800 K and annealed under stress near 3,300 K into Highly Oriented Pyrolytic Graphite (HOPG) with interplanar angular spread below 1 degree.
Because orbital ring currents in its graphene basal planes oppose applied magnetic fields, pyrolytic graphite exhibits the strongest room-temperature diamagnetism of any bulk solid (χ ≈ −4.5 × 10⁻⁴ perpendicular to the planes), passively levitating over neodymium magnets.
Its extreme thermal anisotropy — conducting heat nearly five times better than copper along the graphene sheets while acting as a thermal insulator perpendicular to them — is used in rocket nozzle throats, heat spreaders, and scanning tunneling microscope calibration.