# Armenian bole

**Bolus armenus*, bole armeniac*

**Known today as.** A fine red clay, colored by iron oxide.

Kind: Mineral

## What was it used for?

Drying and binding: for fluxes, bleeding, and the spitting of blood, and against the plague.

## What does modern science say?

An inert clay; any benefit came from binding the stool.

## Pharmacognosy and toxicology

- **kaolinite and illite**: the clay
- **iron oxides**: the red
- **silica**: 

**Mechanism.** A fine clay that adsorbs water, toxins, and bacteria in the gut and firms the stool, which is the use for fluxes and the same principle as kaolin and the modern diosmectite; dusted on it dries a weeping wound; against the plague it was faith. It can bind drugs taken with it and, in quantity, cause constipation and iron deficiency.

**Dose.** Safe at pharmacopoeial doses; some natural clays carry lead.

**Standing.** Kaolin is in the pharmacopoeias; diosmectite (Smecta) has trials for acute diarrhoea in children; bole itself is obsolete.

## What lore surrounds it?

It belongs to the same family as Lemnian earth, clay from the island of Lemnos stamped with a seal, hence *terra sigillata*, “sealed earth.” In antiquity the raw clay was mixed with goat’s blood before being impressed with a goat’s-head seal. Galen visited Lemnos to watch it dug; Pliny recommended the sealed earth for complaints of the tear ducts, spleen, and kidneys and for heavy menstruation. The trade nearly vanished after antiquity, then revived under the Ottomans from the fourteenth century and was carried across Europe into the nineteenth.

## What did the older authorities say?

**Galen.** Recommended it for the great plague of his day.

## Sources

- Galen, *On the Powers of Simple Medicines*.
- “Lemnian Earth” and “Medicinal clay” (reference articles).
- Dupont, C., and Vernisse, B. (2009). “Anti-diarrheal effects of diosmectite in the treatment of acute diarrhea in children: a review.” *Paediatric Drugs* 11.
- Photos-Jones, E., et al. (2017). “Testing Greco-Roman medicinal minerals: the case of solfataric alum.” *Journal of Archaeological Science: Reports* 10.

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*Armenian bole.* In *Materia Medica*, edited by B. C. P. Statema. Version 1, revised 2026-09-25. The Thinking Press. https://thethinkingpress.org/materia-medica/armenian-bole

Historical description, not medical advice.