A worker operates a hole drill during th

A worker operates a hole drill during the ceremony in which Bolivian President Evo Morales received the first laboratory samples from Uyuni - the largest salt flats in the world, at the state-run Lithium Pilot Plant in Rio Grande on October 29, 2009. Bolivia has half of the world's known reserves of lithium -- a key mineral used in medicine and especially in rechargeable batteries, as well as everything from cell phones and laptops to electric cars. With demand for lithium expected to boom in coming years, Bolivia -- one of the poorest countries in South America -- is sitting on something potentially more valuable than a gold mine. Bolivian officials say there are 100 million tonnes of lithium under this desolate, 10,000 square kilometre tourist attraction. AFP PHOTO/Aizar RALDES (Photo credit should read AIZAR RALDES/AFP via Getty Images)