US businessman James Cameron has offered to acquire Kazakh mining giant Eurasian Resources Group (ERG) for $5 billion, according to a letter he sent to the company's board. ERG is preparing to participate in a large-scale expansion of rare earth production in Kazakhstan. Headquartered in Luxembourg, ERG is a producer of copper, cobalt, aluminum, and iron ore, with the Kazakh government holding a 40% stake in the company. Last year, the company stated that it had established a special task force to explore rare earth and rare metal ore deposits in Kazakhstan.