Copper has been added to the US government’s list of critical minerals – the metals deemed vital to the country’s economic and national security. Fortunately, the United States has already accumulated what is the world’s second largest copper stockpile, behind China’s state reserves. It has done so without spending a dollar of federal money. Rather, the copper market has done all the work in the form of a yawning arbitrage gap between the US price traded by the CME and the international price traded on the London Metal Exchange (LME). The pricing differential has already drawn massive amounts of physical copper into ... (full story)