Global silver trade from the 16th to 18th centuries American mining for the early part of the 16th Century. Mining in the Americas became formally industrialized when the process of mercury amalgamation became popularized. Mercury amalgamation was invented by a Spaniard in central Mexico in the 1550s. Historians dispute what individual was the first to invent the process, however most agree that it was a Spaniard. Mercury was the one of the highest costs of production for the Americas, since much of it had to be shipped. The ratio of Mercury to silver produced was about two to one. Furthermore, German miners introduced the stamp mill and lead smelting
Olmecs Olmec chronology came to a head at a 1942 Tuxtla Gutierrez conference, where Alfonso Caso declared that the Olmecs were the "mother culture" (""cultura madre"") of Mesoamerica. Shortly after the conference, radiocarbon dating proved the antiquity of the Olmec civilization, although the "mother culture" question generated considerable debate even 60 years later. The name "Olmec" means "rubber people" in Nahuatl, the language of the Aztec, and was the Aztec name for the people who lived in the Gulf Lowlands in the 15th and 16th centuries, some 2000 years after the Olmec culture died out. The term "rubber people" refers to