Visiting the Halls of Gems and Minerals? All visitors are required to join a virtual line once onsite.
Part of Hall of Planet Earth.
AMNH/R.Mickens
Coal is the most abundant fossil fuel. It forms when dead and decaying plants are buried in swamps and marshes. Over time, as the material is buried, increased temperature and pressure convert it into peat, then lignite, then bituminous coal, and finally, anthracite coal.
Provided by Pittsburgh Research Center,
Bureau of Mines, Pittsburgh, Pennsylvania