Latin ferrum. Iron was used prehistorically:
Iron is a relatively abundant element in the universe. It is found in the sun and many types of stars in considerable quantity. Its nuclei are very stable. Iron is a principal component of a meteorite class known as siderites and is a minor constituent of the other two meteorite classes. The core of the earth -- 2150 miles in radius -- is thought to be largely composed of iron with about 10 percent occluded hydrogen. The metal is the fourth most abundant element, by weight that makes up the crust of the earth.
The most common ore is hematite, which is frequently seen as black sands along beaches and banks of streams.
Iron is a vital constituent of plant and animal life and works as an oxygen carrier in hemoglobin.
Taconite is becoming increasingly important as a commercial ore. The pure metal is not often encountered in commerce, but is usually alloyed with carbon or other metals.
Common iron is a mixture of four isotopes. Ten other isotopes are known to exist.