Carbon dioxide Quote by Anonymous

““While iron oxide makes up over 6% of the Earth’s crust, it took a long time for mankind to figure out how to convert dirt into something as useful as steel. The first smelting of iron from ore was probably accidental when some iron-bearing ore was mixed in with the copper ore during the smelting of copper. Iron ore is composed mostly of various iron oxides which need to be reduced – have oxygen removed – to form metallic iron. The iron ore was mixed with charcoal, which is mostly carbon, and fired. The carbon dioxide produced by burning charcoal combines with the hot carbon in the charcoal, forming carbon monoxide. The hot carbon monoxide turns again to carbon dioxide by stealing oxygen from – reducing – the iron oxides, leaving metallic iron behind. But the heat needed for melting copper isn’t nearly sufficient to melt the iron that may be present in the copper ore. The reaction from ore to iron occurs while in a solid state when the iron forms into a solid, ugly mass of spongy metal called a bloom. The bloom’s cavities were full of slag (molten impurities from the smelting) that needed to be removed. Someone must have recognized the spongy mass as a metallic substance, probably by using appropriate scientific methodology such as hitting it with a rock. Eventually, the bloom was processed by heating it to the slag’s melting point and hammering on it until all of the slag had squirted out. This would be hard, dangerous and resource-intensive work as the iron was reheated and beaten over and over to produce wrought iron. This process was the way iron was made from late B.C. to early A.D.””

— Anonymous