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The iron and steel industry forms the base of all other industries and therefore, it is called a basic industry. It is basic because it provides raw material for other industries such as machine tools used for further production. It may also be called a heavy industry because it uses large quantities of bulky raw materials and its products are also heavy.

Iron is extracted from iron ore by smelting in a blast furnace with carbon (coke) and limestone. The molten iron is cooled and moulded to form pig iron which is used for converting into steel by adding strengthening materials like manganese.

The large integrated steel industry is traditionally located close to the sources of raw materials – iron ore, coal, manganese and limestone – or at places where these could be easily brought, e.g., near ports. But in mini steel mills access to markets is more important than inputs. These are less expensive to build and operate and can be located near markets because of the abundance of scrap metal, which is the main input. Traditionally, most of the steel was produced at large integrated plants, but mini mills are limited to just one-step process steel making – and are gaining ground.

The industry is one of the most complex and capital-intensive industries and is concentrated in the advanced countries of North America, Europe and Asia.

The important steel centres are Sera Thorne, Port Talbot, Birmingham and Sheffield in the U.K.; Duisburg, Dortmund, and Essen in Germany; Le Creusot and St. Etienne in France; and Moscow, St. Petersburg, Lipetsk, Tula, in Russia and Krivoi Rog, and Donetsk in Ukraine. In Asia, major steel producing centres are Jamshedpur, Durgapur, Rourkela, Bhilai, Bokaro, Salem, Visakhapatnam and Bhadravati in India.

Which of the following industry forms the base of all other industries?