Tiny Mining

Cinnabar, a naturally occurring mercuric sulfide (HgS), has long been used in Chinese mineral medicine for more than 2000 years (cinnabar as a sedative).
Alongside arsenic used within elixirs of immortality and elixir poisoning (both also can preserve the dead).
The Almaden mercury mines (in Spain) are the oldest (2,000 years) continuously active mines in the world. They played an important role during the colonial period because mercury was used in America in the amalgam method to extract silver and gold.

Toxicology and location

Most of the metallic mercury will accumulate in your kidneys, but some metallic mercury can also accumulate in the brain. Most of the metallic mercury absorbed into the body eventually leaves in the urine and feces, while smaller amounts leave the body in the exhaled breath.
Elemental and methylmercury are toxic to the central and peripheral nervous systems. The inhalation of mercury vapour can produce harmful effects on the nervous, digestive and immune systems, lungs and kidneys, and may be fatal. The inorganic salts of mercury are corrosive to the skin, eyes and gastrointestinal tract, and may induce kidney toxicity if ingested.
Alice in Wonderland: Erethism, also known as erethism mercurialis, mad hatter disease, or mad hatter syndrome, is a neurological disorder which affects the whole central nervous system, as well as a symptom complex, derived from mercury poisoning. Erethism is characterized by behavioral changes such as irritability, low self-confidence, depression, apathy, shyness and timidity, and in some extreme cases with prolonged exposure to mercury vapors, delirium, personality changes and memory loss.

Insufficiency / Mining Side Effects

None

Private mining applications

Chinese traditional medicine
Conferring immortality

Industrial scale mining

Mercury mining is no longer profitable, but its use continues within illegal, solo gold mining operations