Iron

A relatively abundant element in the universe, Iron is found in many types of stars in considerable quantity. Its nuclei are very stable, and it is a principal component of a meteorite class known as siderites and is a minor constituent of the other two meteorite classes. Many planets have iron cores. A planet with an overabundance of iron and little rocky mantle is known as an iron planet.

Iron is a vital constituent of many types of plant and animal life. The pure metal is not often encountered in commerce, but is usually alloyed with carbon or other metals.