Coal is organic. It is a mineral formed from the remains of land-based plants buried hundreds of millions of years ago and subjected to tremendous heat and pressure.


Coalification has an important bearing on coal's physical and chemical properties and is referred to as the “rank” of the coal. In general, the longer the organic material is subjected to heat and pressure, the higher its rank and the more carbon content will be contained per unit of weight. Ranking is determined by the degree of transformation of the original plant material to carbon. The ranks of coals, from those with the least carbon to those with the most carbon, are lignite, subbituminous, bituminous, and anthracite.

Coal types

Lignite and subbituminous coal (brown coal) are low-ranked coals

Bituminous coal and anthracite (hard coals) are high-ranked coals

Figure 1: How does one type of coal differ from another?

Illustration of coal ranking

Photo of an Illustration of coal ranking
Source: Coal Information, International Energy Agency


Typical use

Low-ranked -

Lignite and subbituminous coal (brown coal)

electricity generation

High-ranked –

Bituminous coal and anthracite (hard coals)

thermal purposes

Premium-grade bituminous
(metallurgical coal, coking coal, or steelmaking coal)

Coal is used to create coke, which is a key ingredient in iron and steelmaking.


Anthracite, the highest-ranked coal (smokeless)

metallurgical purposes or sometimes for household cooking and heating fuel

Coal is classified according to:

  • energy value – how much energy is released when coal is burned
  • degree of transformation into carbon
  • moisture content – coals high in carbon and low in moisture are ranked the highest
  • composition – coal is predominantly carbon but may also contain varying amounts of hydrogen, oxygen, nitrogen and sulphur

Coal mining in Alberta

Mining in Alberta is regulated by the Alberta Energy Regulator. Mining activities and reclamation are subject to review and approval through Alberta Environment and Protected Areas.Jobs, Economy and Trade is responsible for mine safety.

Environmental management is an important part of developing, running and closing down a mine. Mining companies develop and carry out plans to minimize impacts on air, land, water and wildlife. Companies use a variety of techniques to reclaim and restore mined lands.


Connect with the Coal and Mineral Development Unit:

Hours: 8:15 am to noon and 1 pm to 4 pm (open Monday to Friday, closed statutory holidays)
Phone: 780-427-7707
Toll free: 310-0000 before the phone number (in Alberta)
Email: [email protected]


Alberta Energy and Minerals
Coal and Mineral Development Unit
North Petroleum Plaza
9945 108 Street *
Edmonton, Alberta  T5K 2G6

* Couriers, please report to the 2nd floor.

Calgary (drop-off location only)

Alberta Energy and Minerals
300, 801 6 Avenue SW
Calgary, Alberta  T2P 3W2