# Cinnabar

**Minium*, vermilion*

**Known today as.** Mercury sulfide.

Kind: Mineral  
Poisoning: Mercury, arsenic, lead, and antimony (https://thethinkingpress.org/materia-medica/poisons/heavy-metal)  
Deadly: yes

> **Deadly.** Poisonous; deadly when heated.

## What was it used for?

A red pigment; in China an ingredient of elixirs of immortality; in the West in fumigations and ointments for the pox.

## What does modern science say?

Its mercury is poisonous, especially heated. The mineral is nearly insoluble, so swallowed cinnabar does less harm than its reputation; heated, it gives off mercury vapour, which destroys the nerves, and the shaking, loosened teeth, and madness of the mercury miners were known to the Romans. It remains in some Chinese and Ayurvedic preparations, against the advice of every regulator.

## Pharmacognosy and toxicology

- **mercury sulfide**: 

**Mechanism.** Nearly insoluble; the danger is the mercury vapour when it is heated.

**Dose.** Grams by mouth have been taken in Chinese medicine with measurable harm; heating is far worse.

**Standing.** Still in some Chinese and Ayurvedic preparations, against the advice of regulators.

## What lore surrounds it?

The mines of Almadén in Spain, worked from Roman times until 2002, were a death sentence for the slaves and convicts sent there; vermilion from them painted the walls of Pompeii and the manuscripts of the Middle Ages. The Maya covered the dead with it: the Red Queen of Palenque, buried in the seventh century, was found under a layer of cinnabar powder.

## What did the older authorities say?

**Pliny.** Describes the Spanish mines of Sisapo and complains of the confusion between cinnabar and the resin called dragon’s blood (see [Dragon’s blood](https://thethinkingpress.org/materia-medica/dragons-blood)).

**Theophrastus.** The oldest Greek account, *On Stones*, describes the cinnabar of Spain and of Colchis, and the washing of the ore for the pigment.

**The Chinese alchemists.** Made cinnabar the chief ingredient of the elixirs of immortality, since mercury can be drawn from it by fire and returned to it: the First Emperor is said to have died of such elixirs in 210 BC, and his tomb to hold rivers of mercury.

## Sources

- Pliny, *Natural History* XXXIII.
- Theophrastus, *On Stones*.
- Liu, J., et al. (2008). “Mercury in traditional medicines: is cinnabar toxicologically similar to common mercurials?” *Experimental Biology and Medicine* 233.
- Liu, J., et al. (2008). *Experimental Biology and Medicine* 233.

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*Cinnabar.* In *Materia Medica*, edited by B. C. P. Statema. Version 1, revised 2026-10-01. The Thinking Press. https://thethinkingpress.org/materia-medica/cinnabar

Historical description, not medical advice.