Rio Tinto is creeping its way towards control of Canada’s Ivanhoe Mines at a slow but relentless pace, drawing investors’ attentions away from a multi-billion dollar mining transaction that could be as significant for Rio as Canada’s PotashCorp looks to be for BHP Billiton. Over the past six months a conflict has erupted between Rio and Ivanhoe, developers of a new copper project in Mongolia that many analysts consider to be one of the best in the world.