Coal comes from ancient plants that died hundreds of millions of years ago, were buried under mud and sand, and were slowly “cooked” by heat and pressure deep underground into a carbon‑rich rock.

How coal originally forms

  • Around 300–360 million years ago, Earth had vast swampy forests full of ferns, trees, and other lush plants.
  • When these plants died, they fell into oxygen-poor water and mud, so they did not fully rot away and instead built up thick, soggy layers of plant material called peat.

From peat to coal

  • Over long periods, floods and geological changes buried the peat under layers of sediment like sand, silt, and clay.
  • As burial depth increased, the weight of these layers squeezed out water and gases, and heat and pressure transformed the peat into coal in a process called coalification.

Different types of coal

  • With more heat and pressure over longer time, peat first becomes lignite (soft, low carbon), then bituminous coal, and eventually anthracite (hard, high carbon, almost pure carbon).
  • These types differ in color, hardness, and how much energy they release when burned, which is why some are preferred for electricity and others for industry.

Where coal is found today

  • Coal occurs in underground layers called coal seams or coal beds, usually sandwiched between other sedimentary rocks formed in those ancient swamp areas.
  • Major coal regions today include large basins in North America, Europe, Asia, and elsewhere where those ancient swamps once existed.

How humans get coal

  • Coal is extracted mainly by surface mining (removing rock and soil above shallow seams) or underground mining (tunnels and shafts to deeper seams).
  • After mining, coal is transported by rail, barge, truck, or conveyor to power plants and industrial users, where it is burned for electricity and heat.

Information gathered from public forums or data available on the internet and portrayed here.