A worker scoops industrial scrap materials, collected from discarded electronic items, at Dowa Holdings Co's Eco-System Recycling Co, a recycling plant, in Honjo, north of Tokyo. 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.