I did a mine tour. We first visited a market to buy dynamite, coca leaves, and soda as gifts for miners we may encounter. Tunnel areas are run by different cooperatives. It was interesting and humbling. Each coop has a devil statue in the mine they pay weekly respect to for keeping them safe.
At 4500 meters, it's best advised to take an altitude sickness pill 12 hours before your trip to Potosi if coming in quickly from surrounding areas.
We also went to a bar for drinks and found many locals playing cards at tables, drinking hot lemonade with singani (Bolivian clear Brandy).
Here's a BBC article about the mines, devils:
<a href="https://www.bbc.com/news/magazine-29448079" rel="nofollow">https://www.bbc.com/news/magazine-29448079</a>