South America’s mining industry supplies half the world with copper. The world’s largest mines are located in the Andes. Yet just when copper production began there has remained unclear, until now. Very few artefacts from the early high cultures in Peru, Chile, and Bolivia have been preserved. Now, however, researchers of the Paul Scherrer Institute PSI in Villigen, Switzerland, are on the trail of this mystery. Through analysis of ice from the Illimani glacier in the Bolivian Andes, they found out that by around 700 BC, copper was already being mined and smelted in South America. Their findings are published in Scientific Reports, an online journal of the Nature Publishing Group.