Cerro Matoso mine

The Cerro Matoso mine in northwest of Colombia is one of the largest open-pit ferronickel mines in the world. and the largest mine of South America, containing the largest nickel reserve in Colombia. It is operated by Cerro Matoso S.A., a company that was owned by Hanna Company and the Instituto de Fomento Industrial (IFI), then by Shell, Billiton, and then the Anglo-Australian multinational BHP, since 2015 is owned by South32. There have been allegations that the mine's operations have caused heavy metal pollution affecting especially local indigenous Zenu and Afro-Descendant residents. These allegations have been rejected by Cerro Matoso on the basis of the available scientific and medical evidence. In March 2018 a Review Chamber of the Constitutional Court of Colombia ordered Cerro Matoso to pay damages to local communities. This decision was reversed partially in September 2018 by the Plenary Chamber of the Constitutional Court on the basis that it did not comply with constitutional precedent for payment of damages and noting that there was no evidence of a direct correlation between the mining operations and the alleged damages.