The stages of this trend proceed from plant debris through peat, lignite, sub-bituminous coal, bituminous coal, to anthracite coal.
Takes millions of years to convert peat to anthracite caol.
Ranks of Coal Lignite Subbituminous Bituminous Anthracite Time of Formation 7000 BTU/lb 9,000 BTU/lb 12,000 BTU/lb 15,000 BTU/lb Low T, P High T, P Formation Conditions Lowest Grade U.S. Coal Highest Grade U.S. Coal % C
Mine subsidence has been reported in Pekin, Bartonville and in areas around West Peoria.
If you own property in an area of Illinois where mining once occurred, you may want to consider insurance against loss from mine subsidence. This coverage is available from all insurance companies licensed in the State of Illinois.