TOPSHOT - Escondida copper mine miners on strike block a road in Antofagasta, Chile, on February 15, 2017. Workers at the world's largest copper mine, BHP Billiton's Escondida in Chile, began an indefinite strike on February 9 to demand pay increases, prompting concerns on world commodity markets. / AFP / Martin BERNETTI (Photo credit should read MARTIN BERNETTI/AFP/Getty Images)