Another industrial metal is in the spotlight, once again due to President Trump. Copper prices are rallying after Trump instructed the Commerce Department to investigate imposing tariffs on imports of the metal.

Tariffs, if they are imposed, could boost U.S. production of a valuable resource but also raise costs for automakers, construction companies and others.

President Donald Trump opened yet another front on Tuesday in his assault on global trade norms, ordering a probe into potential new tariffs on copper imports to rebuild U.S. production of a metal critical to electric vehicles,