How cinnabar is mined
This soft scarlet rock has a specific gravity of 8.1, extremely high for a mineral that is not a metal.
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- things downstream
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The short version
Hot water rising through cracked rock near recent volcanic activity leaves cinnabar behind as bright red coatings and vein fillings. Miners follow those veins through tunnels, sometimes hundreds of meters down. Even rich rock is mostly waste, since the best mercury ores hold only 2.5% of the metal. Cinnabar is mercury sulfide, the main source of mercury.
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Trace the red veins
Cinnabar forms at shallow depth, below about 200 degrees Celsius, where hot fluids cool in fractured rock. Its color makes it easy to spot in the field, usually alongside quartz, dolomite, calcite or barite.
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Tunnel along the ore
Miners drive shafts and galleries to reach the deposit. The old lower levels at Idrija in Slovenia extend almost 400 meters down. Mining this ore has long been a cause of mercury poisoning, and the rock itself counts as a toxic material.
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Bring up the rock
Broken ore leaves the mine for crushing, ahead of the furnace. Grades run from about 0.1% mercury in lean concentrated deposits to 2.5% in the richest.
Worth repeating
- A woman buried in the 7th-century tomb of the Red Queen at Palenque was covered in bright red cinnabar powder.
- Cinnabar has the second-highest refractive index of any mineral.
- Chinese carved lacquerware got its famous red from cinnabar, a technique that seems to date to the Song dynasty.
Where it goes next
Cinnabar feeds 1 line directly and reaches 2 things in total.
Further down the line
Keep walking
Sources
These sources say little about the factory steps themselves, so parts of this line are a general description. Treat the details with care, and tell us if you know better.
Cite this page: "How cinnabar is mined." Assembly Line, 2026-11-03. https://assemblyline.org/make/cinnabar