64%, highlighting São Paulo (24.6%) and Espírito Santo (21.0%). Mining In mineral production, in 2017, Minas Gerais was the country's largest producer of iron (277 million tons worth R $37.2 billion), gold (29.3 tons for a value of R $3.6 billion), zinc (400 thousand tons for a value of R $351 million) and niobium (in the form of hydrochloride) (131 thousand tons for a value of R $254 million). In addition, Minas was the second largest producer of aluminum (bauxite) (1.47 million tons at a value of R $105 million), third of manganese (296 thousand tons to a value of R $32 million) and 5th of tin (206 tons worth R $4.7 million). Minas Gerais had 47.19% of the value of the production of minerals marketed in Brazil (first place), with R $41.7 billion. The state has the largest production of various gemstones in the country. In aquamarine, Minas Gerais produces the most valuable stones in the world. In diamond, Brazil was the world's largest producer of diamonds from 1730 to 1870, mining occurred for the first time in the Serra da Canastra, region of Diamantina, even lowering the price of stone in everyone due to excess production. Minas Gerais continues to extract diamonds, in addition to having larger or smaller scale productions of agate, emerald, garnet, jasper and Sapphire. Topaz and tourmaline stand out. In topaz, Brazil has the most valuable variety in the world, imperial topaz, only produced in Ouro Preto. In addition, the country is the world's leading producer of topaz. It's also one of the world's largest tourmaline producers. Industry In the Southeast region, the industrialization of the country began, making the transformation industry the main source of income and work in its states. The state of São Paulo became the largest industrial park in South America. The Southeast Region has 53% of the industrial GDP of Brazil. The main industrial activities in the region are: Iron and steel industry and metallurgy: It's in this region that the first industry of this type is located, the Companhia Siderúrgica Nacional, in the city of Volta Redonda, due to its proximity to a large area of iron mining, the so-called "iron quadrilateral", in the state of Minas Gerais. The Usiminas, in Ipatinga, which today is the largest crude steel producer in the country, and the Companhia Siderúrgica de Tubarão, in Vitória, Espírito Santo, are also installed in the