THREE of the world’s biggest mining groups have announced an alliance with commodity trader Glencore International AG to set up global Internet marketplaces for trading commodities, starting with coal. Rio Tinto Plc/Ltd, Anglo American Plc, Billiton Plc and Swiss-based Glencore said they would join Internet firm Accel-KKR Company LLC to develop online marketplaces for trading base metals, bulk ores and bulk alloys. The first would serve global producers and consumers of thermal coal, the parties said in a joint statement. – Reuters