Coal Terms

Coal Terms

Coal is a combustible organic rock composed principally of consolidated and chemically altered vegetal remains. Geologic process, working over vast spans of time, compressed and altered decaying plant material that resulted in an increase of the percentage of carbon. With increasing heat and pressure different ranks of coal can occur: lignite (the softest), subbituminous, bituminous, and anthracite (the hardest).

Anthracite Dense, shiny coal that has a high carbon content and little volatile matter and burns with a clean flame.

Ash Impurities, consisting of silica, iron, alumina and other incombustible matter that are contained in coal.

Bituminous A soft coal which yields, when heated, a considerable amount of volatile bituminous matter. It burns with a yellow smoky flame.

Braitch Hole Abandoned coal mine tunnel, sometimes called an "airhole".

BTU (British thermal unit) The amount of heat needed to raise the temperature of 1 pound of water by 1 degree fahrenheit.

Coalbank A hill made of coal or coal effluvium.

Coke A solid residue derived from low-ash, low-sulfur bituminous coal from which the volatile constituents are driven off by baking in an oven at temperatures as high as 2000 degrees.

Colliery A coal mine and its collected buildings.

Deep Mine An underground operation in which coal is extracted through shafts.

Hard Coal Anthracite coal.

Highwall The unexcavated face of exposed over-burden and coal in a surface mine.

Lignite The lowest rank of coal, used almost exclusively as fuel for steam-electric power generation.

Overburden Any material that overlies a coal deposit.

Preparation Plant A facility at which coal is crushed, screened and mechanically cleaned.

Reclamation The process of restoring a surface mine site to its original contour, function and appearance.

Roof The rock immediately above the coal seam.

Seam A bed of coal lying between a roof and the floor.

Slate A fine-grained metamorphic rock that can be split into thin layers. Coal is often found within those layers.

Slurry A mixture of water and any of several finely crushed solids especially cement, clay, or coal.

Soft Coal Bituminous coal.

Strip Mine An Open coal mine whose seams or outcrops run close to ground level and are exposed by the removal of topsoil and overburden.

Sulfur Diamonds Pyritic crystals of sulfur, found among the slate and coal refuse on the coalbanks.

Anthracite	Dense, shiny coal that has a high carbon content and little volatile matter and burns with a clean flame.
Ash	Impurities, consisting of silica, iron, alumina and other incombustible matter that are contained in coal.
Bituminous	A soft coal which yields, when heated, a considerable amount of volatile bituminous matter. It burns with a yellow smoky flame.
Braitch Hole	Abandoned coal mine tunnel, sometimes called an "airhole".
BTU (British thermal unit)	The amount of heat needed to raise the temperature of 1 pound of water by 1 degree fahrenheit.
Coalbank	A hill made of coal or coal effluvium.
Coke	A solid residue derived from low-ash, low-sulfur bituminous coal from which the volatile constituents are driven off by baking in an oven at temperatures as high as 2000 degrees.
Colliery	A coal mine and its collected buildings.
Deep Mine	An underground operation in which coal is extracted through shafts.
Hard Coal	Anthracite coal.
Highwall	The unexcavated face of exposed over-burden and coal in a surface mine.
Lignite	The lowest rank of coal, used almost exclusively as fuel for steam-electric power generation.
Overburden	Any material that overlies a coal deposit.
Preparation Plant	A facility at which coal is crushed, screened and mechanically cleaned.
Reclamation	The process of restoring a surface mine site to its original contour, function and appearance.
Roof	The rock immediately above the coal seam.
Seam	A bed of coal lying between a roof and the floor.
Slate	A fine-grained metamorphic rock that can be split into thin layers. Coal is often found within those layers.
Slurry	A mixture of water and any of several finely crushed solids especially cement, clay, or coal.
Soft Coal	Bituminous coal.
Strip Mine	An Open coal mine whose seams or outcrops run close to ground level and are exposed by the removal of topsoil and overburden.
Sulfur Diamonds	Pyritic crystals of sulfur, found among the slate and coal refuse on the coalbanks.