Coca is also a stimulant and an appetite suppressant. The silver miners go into the mines for like 48 hours at a time and they chew the leaves so they can keep working without stopping. Sounds like an absolute nightmare. I was down there for two hours and I could barely keep it together.
This is one of these weird instances where one language takes a generic word from another language and gives it a specific meaning. In this case, "altiplano" only means plateau in Spanish, and the Spanish name for this region is Altiplano Andino (Andean Plateau), akin to the Baja Peninsula from "Baja California" (which means lower California)
Peru literally in north of bolivia...