Do you know what the most common element in the earth as a whole is? It is also the fourth most common element that makes up the crust of the earth. Any guesses? It is produced as a bi-product of the fusion that happens in high-mass stars. It oxidizes in air and is the most widely used metal as well. Let me give you a hint, there was a figurative curtain made out of this substance at the end of World War 2 that separated Eastern and Western Europe. Have you guess it yet? It is iron!
Iron, or Fe, holds the atomic number of 26 on the periodic table of elements. That means there are 26 protons, or positively charged particles, found within the nucleus of a single iron atom. When iron and air combine, we call that oxidation. That chemical process creates many various forms of oxidized iron. The one we most commonly notice is called rust. You can see rust on cars in wetter climates, but you do not see it nearly as much in dry, desert areas. That is because aside from just oxygen, iron needs water to rust as well. So anything that you leave out in the rain, if it is iron, will potentially be covered in a reddish rust a ways down the road.
Iron had been used through history, though not nearly as much as bronze or copper. The first iron production began in the Middle Bronze Age. Scientists and archaeologists have recovered iron beads that they have dated all the way back to 3500 B.C. People soon began to realize the potential of this new metal and started experimenting and learning how to refine and use this metal. In fact, the next age classification of humanity was the Iron Age. Because iron is created in the sky as a stellar fusion, iron that came down to earth in the form of a meteorite was considered very sacred, because it was thought to have come straight from the heavens. Meteoric iron would be used to make weapons or tools in hopes to have some heavenly protection in battle, or it would be used to create whole statues or specimens to be placed in churches.
Today, iron is the most widely used metal. It has a low production cost, but pure iron is actually quite soft. Thus, it is most commonly found in the form of steel. Steel is simply a combination of iron and other materials, such as carbon, manganese, or tungsten. By combining these elements together, iron can become quite strong, making it a desirable choice of material for things like construction equipment, cars, ships, and even those fancy entry doors that guard off private neighborhoods or big expensive houses.
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