Lead is mined in parts of the Americas, Central Asia, Asia Minor, and in the Balkans. Ore with lead normally also contains either Zinc, Silver, or Copper and can be found in nature as Lead Oxide, Lead Dioxide, Galena (PbS), Anglesite (PbS04), Cerrusite (PbCO3), or Minum (Pb3O4). During extraction contaminants are oxidized to isolate the Lead. During the 20th century the use of lead was a double edged sword. Famously Thomas Midgley Jr (bottom left) invented Tetraethyllead which improved the performance of motor vehicles, but it was later uncovered to the public through the work Dr Clair Cameron Patterson (bottom right) that the use of this compound in cars was not only inducing Lead poisoning in countless people but was throwing the natural geochemistry of the ocean and air out of order and was to blame for rising ocean acidity worldwide. Lead is now banned for use in automobile fuel because of the research of Dr Patterson and others.