Electricity production is the primary use of coal in the United States. Most of the coal mined in the United States is transported to a power plant, crushed to a very small particle size, and burned. Heat from the burning coal is used to produce steam, which turns a generator to produce electricity. Most of the…

Plant debris is a fragile material compared to the mineral materials that make up other rocks. As plant debris is exposed to the heat and pressure of burial, it changes in composition and properties. The “rank” of a coal is a measure of how much change has occurred. Sometimes the term “organic metamorphism” is used…

Coal forms from the accumulation of plant debris, usually in a swamp environment. When a plant dies and falls into the swamp, the standing water of the swamp protects it from decay. Swamp waters are usually deficient in oxygen, which would react with the plant debris and cause it to decay. This lack of oxygen…

The highest rank of coal. It is a hard, brittle, and black lustrous coal, often referred to as hard coal, containing a high percentage of fixed carbon and a low percentage of volatile matter. What is Coal? Coal is an organic sedimentary rock that forms from the accumulation and preservation of plant materials, usually in a swamp environment.…