USES OF IRON
The uses of iron ore are so well known that their enumeration is hardly necessary. From iron ore are manufactured cast iron, wrought iron, and steel. By the addition of one or more other elements, chiefly silicon, carbon, chromium, nickel, manganese, vanadium, sulphur, and phosphorus, in quantities less than 5 per cent. and usually less than 1 per cent., various qualities, such as hardness, toughness, elasticity, durability, brittleness, density, porosity, endurance, resistance to oxidation or corrosion, malleability, and fusibility, can be controlled and given to the cast iron or steel in the desired degree.
The uses of the products of iron ore are so common that the finding of objects which do not contain some of them is difficult. Besides being used as a metal, iron enters into the manufacture of paints (especially red, yellow, and blue), chemicals of various kinds, medicines, coloring matter in glass and pottery, and in the form of specular hematite it is made into jewelry. Considerable amounts of iron ore are also consumed annually for flux in the smelting of silver, copper, lead, and other metalliferous ores.
Iron and its products are more widely used than any other metal; and the yearly production of pig iron makes up 94 to 96 per cent. of the total amount of all the metals produced in the world, and in normal times averages about 80,000,000 tons annually.