After 1800 the silver mines of Potosi became depleted, making tin the main product. This eventually led to a slow economic decline. Still, the mountain continues to be mined for silver to this day. Due to poor worker conditions (lack of protective equipment from the constant inhalation of dust), the miners still have a short life expectancy with most of them contracting silicosis and dying around 40 years of age.
The mine workers chew coca leafs all day, not only does it alleviate sorroche, it also allows them to work long hours without feeling hungry.
If you take a silver mine tour you can offer the mine workers a bag of coca leafs or, if you prefer, some cigarettes or even dynamite.