Of the more than thirteen million individuals in fifty-five developing countries that depend on small-scale gold mining to survive, most employ an ancient and harmful practice called "mercury amalgamation" in order to extract the gold. After panning for gold in local bodies of water, the miners pour gold-bonding mercury into their pans to form a solid paste. They wash off excess mercury into the water and boil down the paste to yield pure gold. The mercury in the water poisons the miners, the communities living downstream, and pollutes the environment. The European Union, the world's largest global exporter of mercury, will soon ban mercury exports, putting tens of millions of artisanal gold miners out of work.
This E-Team has a solution: an inexpensive (~$30), manually powered centrifugal gold extraction device. Based on industrial-size gold centrifuges, the device uses lightweight modern plastics to create a hand crank-based centrifuge capable of extracting gold with little effort and without requiring mercury.
Two competitors exist, but both of their solutions still require the use of at least some mercury.