The Geology of Graphite: Carbon Cooked Under Pressure
Natural graphite forms when carbon-rich rock is metamorphosed under heat and pressure, a different origin from the synthetic graphite batteries also use.
Natural graphite is not simply carbon that happened to crystallise the layered way, covered in depth on this material’s materials science page. It requires organic or carbon-bearing sedimentary material to be metamorphosed, buried, heated, and compressed over geological time until the carbon reorganises into graphite’s hexagonal sheets.
Flake versus amorphous graphite
Two main natural graphite types reach the market: flake graphite, formed in metamorphic rocks like marble and schist where conditions allowed large, well-ordered crystal flakes to grow, and amorphous graphite, formed from coal or other carbon-rich sediment under lower-grade metamorphism, producing much finer, less-ordered material. Flake graphite, with its larger, more perfect layered crystals, is the preferred feedstock for the battery anode applications covered on this material’s application-wise page, a direct consequence of how cleanly its layers can be processed into spherical anode particles.
Synthetic graphite is not mined at all
A majority of world graphite supply, roughly 65% by the dashboard’s own figures, is synthetic, made by heating petroleum coke or coal tar pitch to extremely high temperatures until it graphitises, an industrial process rather than a mining operation, covered in more depth on this material’s mining page. This means “graphite supply” genuinely spans two different production systems, one geological and one purely industrial, feeding into the same end markets.
Sources: deposit-type framing draws on standard economic geology references (USGS Mineral Commodity Summaries); production figures reference the production data elsewhere on this site.