Iron

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Iron is a chemical element with the symbol Fe() and the atomic number 26. It belongs to the transition metals, which in the periodic table form the 8th subgroup (iron-platinum group), after the new count the group 8 (iron group). In terms of mass fraction (ppmw), iron is the fourth most abundant element in the earth's crust after oxygen, silicon and aluminum and the most abundant metal after aluminum.

On Earth, except in various ores and iron minerals, it occurs in the form of an alloy in iron meteorites. Even before the Iron Age, some 3000 years before our era, cult objects, tools or weapons were made from these. In particular, the iron ores magnetite, hematite and siderite are degraded.

Chemically pure iron is a silver-white, relatively soft, stretchy, quite reactive metal. It is attracted to magnets as a ferromagnetic material and can form its own magnetic fields. Pure iron is relatively rarely used in practice, but it enters into alloys with about 80 other elements, the main one being steel and cast iron. These are of irreplaceable economic and technical importance for many industries such as automotive, mechanical engineering, construction, transport and energy production.

Iron is an essential trace element for almost all living beings. In animals, it is a component of the blood in the form of hemoglobin in the red blood cells and also important for the formation of proteins and enzymes.

Use of terms and origin
In addition to the chemical element as pure iron, the practically much more important iron alloys were usually called "iron" (e.g., wrought iron). In the 20th century, the term “steel” prevailed for forging iron alloys with a carbon content of less than 2 percent by mass. In the case of higher carbon content, the term “cast iron” still applies.

Until the 21st. In the 19th century it was assumed by linguists (such as Rudolf Thurneysen or Stefan Schumacher) that the Celtic and Germanic word for iron (Celtic *isarnon, Germanic *isarna) had been borrowed from Illyrian. Also because of the contrast to the softer bronze a kinship of *isarnon to Latin ira "wrath, fierceness" was represented. The New High German word iron (from Middle High German īsen, and to īsīn "eisern") is derived from Old High German īsa(r)n, from Urgent German *īsarnan or *eisarna-, and this from Gallic *īsarnon. *isarnan and isarnon continue in Germanic languages (English iron, North Frisian joorn, West Frisian izer, Dutch IJzer) as well as in Celtic languages (Breton houarn, kymr. haearn, Irish and Scottish Gaelic iarann, Manx yiarn). Since the end of the 20th century, century also other ways of borrowing than possible anno