The Cerro Rico is a mountain 4800 meters high located in the city of Potosí, in the Bolivian Andes, famous because during the time of the Spanish colony it had the most important silver reserve in the world. Since then the exploitation of silver never stopped and thousands of workers have died and are still dying entering the mine to open new veins with dynamite and removing tons of earth mixed with minerals. This material is separated in the ''ingenios'', mineral industries where mills use the hydraulic force of water coming from the artificial lagoons of Kari Kari. It is a hard and dangerous work that causes about 300 deaths each year. Working conditions are prohibitive and life expectancy of miners reaches 45 years. Despite this, every morning men and children ‘’go down into hell’’ to earn a living. They die from silicosis, a lung disease caused by breathing tiny bits of silica present in the rock. In order to keep working in such a hostile environment, where oxygen is very low and it is barely possible to breathe, they chew coca leaves and assume alcohol on a daily basis. Miners are very superstitious, in fact inside the mines there are many statues of "el Tio", the uncle, a deity representing the devil, considered the owner of the mines. They make daily offerings, "challas", such as cigarettes, coca leaves and alcohol to the various statues and sacrifice a lama spreading his blood at the entrance of the mines. They believe that, if not properly fed, ‘’el Tio’’ will take his own revenge by hiding the silver or causing deaths.