List of countries by coal reserves
32 rows· Background. Coal is a combustible black or brownishblack sedimentary rock, formed as rock strata called coal seams. Coal is mostly carbon with variable amounts of other elements; chiefly hydrogen, sulfur, oxygen, and nitrogen. As a fossil fuel burned for heat, coal supplies about a quarter of the world''s primary energy and twofifths of its electricity. The largest consumer and importer of ...