By the mid-1900s, much of the mining production in Pachuca and Real del Monte was controlled by U.S. based interests such as the United States Mining Smelting and Refining Company.
К середине 1900-х годов, большую часть горного производства в Пачуке и Реаль-дель-Монте находились под контролем американских компаний, таких как United States Mining Smelting and Refining Company.