carried out in Rio Grande do Sul and Santa Catarina, greatly increased previously known coal reserves between 1970 and 1986 (mainly between 1978 and 1983). Then good quality coal, suitable for use in metallurgy and in large volumes (seven billion tons), was discovered in several deposits in Rio Grande do Sul (Morungava, Chico Lomã, Santa Teresinha), but at relatively great depths (up to 1,200 m), which has prevented its use until now. In 2011, coal represented only 5.6% of the energy consumed in Brazil, but it is an important strategic source, which can be activated when, for example, the water levels in the dams are very low, reducing the excess supply of water. hydroelectric power. This happened in 2013, when several thermoelectric plants were closed, thus maintaining the necessary supply, although at a higher cost. Paraná is the largest producer of oil shale in Brazil. In the city of São Mateus do Sul, there is a plant Petrobras specialized in the production of the material. Approximately 7,800 tons are processed daily. Rio Grande do Sul is an important producer of gemstones. Brazil is the world's largest producer of amethyst and agate, and Rio Grande do Sul is the country's largest producer. Agate has had local extraction since 1830. The largest producer of amethyst in Brazil is the city of Ametista do Sul. This stone was very rare and expensive throughout the world, until the discovery of large deposits in Brazil, which caused a considerable drop in its value. Industry The region concentrates 20% of the industrial GDP of the country. In 2019, Paraná was the second largest vehicle producer in the country (Brazil is one of the 10 largest vehicle producers in the world). Paraná has in its territory the Volkswagen, Renault, Audi, Volvo and DAF factories; Santa Catarina has GM and BMW plants and Rio Grande do Sul, a GM plant. In the food industry, in 2019, Brazil was the second largest exporter of processed foods in the world, with a value of US$34.1 billion in exports. Regarding the creation of national or multinational companies, Rio Grande do Sul created companies such as Neugebauer, Camil Alimentos, Fruki, Cervejaria Polar, Vinícola Aurora and Vinícola Salton. Santa Catarina created companies such as Sadia and Perdigão (which later merged into BRF), Seara Alimentos (which today belongs to JBS), Aurora, Gomes da Costa, Cervejaria Eisenbahn and Hemmer Alimentos. Paraná created companies such as: