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  2. Coal - Wikipedia

    en.wikipedia.org/wiki/Coal

    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 , sulfur , oxygen , and nitrogen . [ 1 ]

  3. Vitrinite - Wikipedia

    en.wikipedia.org/wiki/Vitrinite

    Vitrinite is a type of maceral, where "macerals" are organic components of coal analogous to the "minerals" of rocks. Vitrinite has a shiny appearance resembling glass (vitreous). It is derived from the cell-wall material or woody tissue of the plants from which coal was formed. Chemically, it is composed of polymers, cellulose and lignin. [1]

  4. Pittsburgh coal seam - Wikipedia

    en.wikipedia.org/wiki/Pittsburgh_coal_seam

    The Pittsburgh coal seam is the thickest and most extensive coal bed in the Appalachian Basin; [1] hence, it is the most economically important coal bed in the eastern United States. The Upper Pennsylvanian Pittsburgh coal bed of the Monongahela Group is extensive and continuous, extending over 11,000 mi 2 through 53 counties.

  5. Geology of the Appalachians - Wikipedia

    en.wikipedia.org/wiki/Geology_of_the_Appalachians

    The Appalachian Basin is one of the most important coal producing regions in the U.S. and one of the largest in the world. Bituminous coal has been mined throughout the last three centuries. Currently, the coal primarily is used within the eastern U.S. or exported for electrical power generation, but some of it is suitable for metallurgical ...

  6. Coal mining - Wikipedia

    en.wikipedia.org/wiki/Coal_mining

    Coal mining is the process of extracting coal from the ground or from a mine. Coal is valued for its energy content and since the 1880s has been widely used to generate electricity. Steel and cement industries use coal as a fuel for extraction of iron from iron ore and for cement production.

  7. Carboniferous - Wikipedia

    en.wikipedia.org/wiki/Carboniferous

    Coal forms when organic matter builds up in waterlogged, anoxic swamps, known as peat mires, and is then buried, compressing the peat into coal. The majority of Earth's coal deposits were formed during the late Carboniferous and early Permian. The plants from which they formed contributed to changes in the Carboniferous Earth's atmosphere. [25]

  8. Coal gasification - Wikipedia

    en.wikipedia.org/wiki/Coal_gasification

    Coal tar and coal tar sludges are frequently denser than water and are present in the environment as a dense non-aqueous phase liquid. In the UK, a number of former gasworks sites have been redeveloped for residential and other uses (including the Millennium Dome), being seen as prime developable land within the confines of city boundaries.

  9. Lignite - Wikipedia

    en.wikipedia.org/wiki/Lignite

    Lignite (derived from Latin lignum meaning 'wood'), often referred to as brown coal, [1] is a soft, brown, combustible sedimentary rock formed from naturally compressed peat. It has a carbon content around 25–35% [ 1 ] [ 2 ] and is considered the lowest rank of coal due to its relatively low heat content .