Note: Chlorhexidine may cause staining of the tooth, tooth filling, and dentures or other mouth appliances. Tetracycline use during tooth development phases (from the last half of pregnancy through eight years of age) may cause permanent discoloration (yellow, gray, brown) of teeth.
What is Coal made of? Coal is made from trees or plants that decayed on the ground for millions of years. The remains of various plants and trees then mixed with the other components of the ground and eventually going through several natural processes making them more like solid rocks.
Coal is a combustible sedimentary rock composed mostly of carbon and hydrocarbons. It is the most abundant fossil fuel produced in the United States, but it is a nonrenewable resource.The energy in coal comes from the energy stored by plants that lived hundreds of millions of years ago in swampy forests.t is the most commonly used type of coal for electric power generation in the United States. It is a dark, hard coal that has a higher heating value than lignite and subbituminous coal, but a lower heating value than anthracite.