Coal the heat and pressure of deep burial causes the loss of water, methane and carbon dioxide and an increase in the proportion of carbon. Thus first lignite (also called "brown coal"), then sub-bituminous coal, bituminous coal, and lastly anthracite (also called "hard coal" or "black coal") may be formed. The wide, shallow seas of the Carboniferous Period provided ideal conditions for coal formation, although coal is known from most geological periods. The exception is the coal gap in the Permian–Triassic extinction event, where coal is rare. Coal is known from Precambrian strata, which predate land plants—this coal is presumed to
Brown coal mining limits in North Bohemia on other foundations than only coal and coal-fired power generation is above all realistic and realisable. We'd also like to discuss the issue of employment with the Prime Minister. It would be good for him to hear that annulling the limits would not bring about a positive impact on employment in the region, but rather the contrary." The mayor of Litvínov, Milan Štovíček, called Rusnok's statement a “dirty trick” played on the population of the Usti region. “I personally see it as the biggest scam on the people since 1989. This is what only totalitarian governments allowed in the past