Magnesium is a metal element denoted by the atomic symbol Mg. It has an atomic number of 12, and an atomic weight of 24.305. It is a silvery-white metal with a melting point of 1202°F (650°C) and a boiling point of 1994°F (1090°C).

Magnesium (Mg) is one of the most abundant structural metals ranking third behind iron and aluminum. Magnesium compounds are found in mineral rocks such as dolomite and magnesite, while the Earth's oceans contain a practically unlimited supply of the metal in the form of dissolved magnesium chloride. One cubic mile of seawater holds some six million tons of the element. The lightest of all the structural metals, magnesium is about one-third lighter than aluminum and gives more strength and stiffness per pound than any other common metal.

Magnesium compounds such as Epsom salts were first prepared in the late 1600s and early 1700s...