TOKYO (Reuters) -Japan's Nippon Steel said on Tuesday it had bought a 30% stake in Canada's Kami iron ore project, forming a joint venture with Australia's Champion Iron and Sojitz to secure high-grade ore supplies for direct reduced iron. Japan's top steelmaker paid C$42 million ($30.2 million) of the total C$150 million consideration through its unit NS Canadian Resources, with the remaining C$108 million to be paid pending an additional investment decision based on a feasibility study. The deal follow ...