Coal - Wikipedia
Coal is a combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams. Coal is mostly carbon with variable amounts of other elements, chiefly hydrogen, …
Coal | Uses, Types, Pollution, & Facts | Britannica
Nov 8, 2025 · Coal is defined as having more than 50 percent by weight (or 70 percent by volume) carbonaceous matter produced by the compaction and hardening of altered plant …
What is coal? | U.S. Geological Survey - USGS.gov
What is coal? Coal is a sedimentary deposit composed predominantly of carbon that is readily combustible. Coal is black or brownish-black, and has a composition that (including inherent …
Coal - National Geographic Society
Nov 15, 2024 · Coal is a nonrenewable fossil fuel that is combusted and used to generate electricity. Mining techniques and combustion are both dangerous to miners and hazardous to …
Coal explained - U.S. Energy Information Administration (EIA)
Oct 24, 2023 · Coal is a combustible black or brownish-black sedimentary rock with a high amount of carbon and hydrocarbons. Coal is classified as a nonrenewable energy source …
What is Coal, How Many Types of Coal ?, What is Coal Used for
Coal is a sedimentary deposit composed predominantly of carbon that is readily combustible. Coal is black or brownish-black, and has a composition that (including inherent moisture) consists of …
Coal - Understand Energy Learning Hub
It is a chemically complex, rock-like hydrocarbon that contains heavy metals (e.g., mercury and lead), sulfur, and radioactive material. It is a huge contributor to climate change, air pollution, …