ABSTRACT
Coal is an impure form of carbon, occurring naturally as a stratified sedimentary rock. The original process of coal formation took place in areas in which there had been luxurious vegetation and especially a preponderance of trees. The decaying process was catalysed by bacteria and the overall conversion from organic plants was also effected by the heat and pressure from overlying rock formations. The conversion process from the decay of organic plants through the stages of peat formation to anthracite, is known as “coalification”; a clumsy word but nevertheless descriptive. The degree of coalification is described by the concept of “rank”. The coal extracted from the coal seam or seams is usually referred to as “run of mine” coal and is a mixture of coal and “dirt bands” associated with the mining conditions from which it is extracted. Coal composition is very important in determining its utilisation and potential for export.
