The U.S. government is taking a minority stake in Lithium Americas, a company that is developing one of the world's largest lithium mines in northern Nevada. The Department of Energy will take a five per cent equity stake in the miner, which is based in Vancouver. It will also take a five per cent stake in the Thacker Pass lithium mining project, a joint venture with General Motors. Shares of Lithium Americas spiked more than 33 per cent before the opening bell Wednesday. U.S. Energy Secretary...