Earth

Iron working

Pure iron is very rare in nature. It can be found more frequently in combination with other elements inside minerals. These minerals are called iron minerals. Among them, the most important ones are haematite, pyrite and siderite. The first stage of iron mineral working occurs in hot furnaces and leads to the creation of a particular product that is called cast iron. The hot furnace is made up of two cone trunks whose bases are interconnected and that have a cylindrical support. The furnace is 20-30 metres high and has an 8-10 metre diameter. Iron minerals, coal and fluxes (special materials that are used to eliminate that part of the minerals that cannot be used) are supplied from the top. (See image “Hot furnace”) From cast iron, through a “de-carburisation” process, steel is obtained. With a further “de-carburisation”, ductile iron is formed. De-carburisation is a cast-iron refining process. Carbon and impurities like silicon, phosphorus, sulphur and manganese are removed from the cast iron.