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 sedimentary organic rock that contains a lot of carbon -- between 40 and 90 percent carbon by weight. Coal is formed by ancient plants and animals accumulating in moist peat bogs. As plants die off in a wet area, they pile up into peat.