Lithium mine on Salar de Uyuni. Satellite image of evaporation ponds (green rectangles near centre) on the southern edge of the Salar de Uyuni salt flat in Bolivia. This is the world's largest salt flat. Lithium-rich brine is pumped into the ponds to evaporate. The salt deposits are processed for the metal lithium, a key component of rechargeable batteries and other electronics. This image was obtained on 12 April 2013, by the Operational Land Imager (OLI) on Landsat 8.