Coal is a combustible sedimentary rock formed predominantly from plant material that has been deposited in ancient marshy environments. Through burial over long periods of geological time, the plant material is transformed by microbial action, pressure and hea...

Australian brown coal or lignite is a low rank, low ash, high moisture content coal. In Australia, brown coal is currently considered unsuitable for export and is used primarily to generate electricity in domestic power stations. Deposits of brown coal in Aust...