Our demand for raw materials is enormous and the mineral and ore mines can hardly keep up with the growing demand. Weirdly, we're surrounded by raw materials! They're in our cars, in the underground tunnels we use to travel to work, in the pavement that leads to our houses, in the bridges we cross, and they're in our homes. In European cities, there are approx. 4.500 kg of iron, 340 kg of aluminum, 200 kg of copper, 40 kg of zinc and 210 kg of lead attributed to each inhabitant.