Miners are operating amid turf wars between rival cartels in Mexico's Chihuahua state, with mining municipalities among the worst affected.
Companies in Chile, Brazil, Ecuador and Peru updated information about their exploration results.
Companies issue corporate updates relating to gold and silver assets in Peru, Uruguay, Chile, Colombia and Mexico.
The investment includes the construction of one lithium plant in Catamarca province and another one in Salta province.
Leftwing Morena presidential candidate Andrés Manuel López Obrador pledges to pay special attention to Mexico's miners to ensure they meet environmental, wage and tax requirements.
The London-based miner, which already produces iron ore and nickel in the country, is reportedly exploring for copper in Mato Grosso and Pará states.