Indium, gallium and hafnium are some of the least-known elements on the periodic table, but New Scientist warns that reserves of these low-profile minerals and others like them might soon be exhausted thanks to the demand for flat screens and other high-tech goods. Scientists who have tried to estimate how long the world's mineral supply can meet global demand have made some gloomy predictions.

Armin Reller, a materials chemist at the University of Augsburg in Germany, estimates that in 10 years the world will run out of...