Piquia dos Baixos in Maranhao has been heavily affected by the iron ore industry, with a smelting plant right inside the village. The Carajas Open Cast Iron Ore mine is the largest iron mine in the World, estimates say the site can be mined at today's rates for another 400 years. In the Amazonian State of Para, Brazil, it is operated by the State owned Vale mining corporation, prevoously CVRD. The company has come under some controversy about the mine, and recently has started expanding the mine on the site of a series of ancient caves.