Urban miners seek gold in mobiles

HONJO: Thinking of throwing out your old cell phone? Think again. Maybe you should mine it first for gold, silver, copper and a host of other metals embedded in the electronics — many of which are enjoying near-record prices. It's called "urban mining", scavenging through the scrap metal in old electronic products in search of such gems as iridium and gold, and it is a growth industry around the world as metal prices skyrocket. The materials recovered are reused in new electronics parts and the gold and other precious metals are melted down and sold as ingots to jewellers and investors as well as back to manufacturers who use gold in the circuit boards of mobile phones because gold conducts electricity even better than copper. "It can be precious or minor metals, we want to recycle whatever we can," said Tadahiko Sekigawa, president of Eco-System Recycling Co which is owned by Dowa Holdings Co Ltd. A tonne of ore from a gold mine produces just 5 grams of gold on average, whereas a tonne of discarded mobile phones can yield 150 grams or more, according to a study by Yokohama Metal Co Ltd, another recycling firm. The same volume of discarded mobile phones also contains around 100 kg of copper and 3 kg of silver, among other metals. Recycling has gained in importance as metals prices hit record highs. Recycling electronics makes sense for Japan which has few natural resources but does have tens of millions of old cell phones and other obsolete consumer electronic gadgets thrown away every year. "To some it's just a mountain of garbage, but for others it's a gold mine," said Nozomu Yamanaka, manager of the Eco-Systems recycling plant where mounds of discarded cell phones and other electronics gadgets are taken apart for their metal value. The scrap electronics and other waste is first sorted and dismantled by hand. It is then immersed in chemicals to dissolve unwanted materials and the remaining metal is refined.