Rio Tinto on Friday said it had moved a step closer to the development of a new copper project in Arizona, one of the few new major known deposits of the metal, with the potential to meet around a quarter of U.S. demand.Miners have been scouring the globe for sources of copper - a mineral they predict will be in high demand as the world shifts toward renewable power and electric vehicles. Resolution Copper, 55% owned by Rio Tinto and 45% by BHP, has spent years waiting for clearance from U.S. authorities to develop the underground mine. On Friday, Rio Tinto said a 90-day public consultation would begin now that the ... (full story)