Brown coal or lignite, as it is also known, is a grade of coal intermediate between coal and peat.
Brown coal contains more moisture and less energy per kilogram than more mature coals.
It also tends to dry and crumble when exposed to air. Brown coal is a second tier fuel that produces significant amounts of smoke. Large deposits are found in the United States, Canada, Germany, and elsewhere, chiefly in Tertiary formations. German Brown coal localities are found from Koln in the west of Germany right across eastwards. The eastern material is not so profitable to mine, and many pits have closed.