The Lost Practice of Orchil Dyeing

Orchil History

Lichen dyeing is an ancient tradition dating back thousands of years and accross disparate cultures of the world. From the Bible (Ezekiel 27:7 KJV): "Fine linen with broidered work from Egypt was that which thou spreadest forth to be thy sail; blue and purple from the isles of Elishah was that which covered thee." One particular lichen dye is of particular note historically -- Orchil.

The name orchil was introduced into England, likely during the 14th century, to denote the dye Roccella dye  first manufactured in Florence known locally as oricello. However, this name has expanded to now include the purple and red dyes made from a wide variety of lichens not exclusively in Rocella.

Orchil (also known as archil, orcein, lacmus, rocella, lichen purple) is a violet dye that does not need a mordant and the color is said by Theophrastus to be even more brilliant than the exorbitant imperial purple, but unlike Tyrian, the color is fairly fugitive unless mordanted with tin. Orchil was primarily obtained from species of rock lichen in the family Roccella. These lichen are common in places like the Canary Islands and other tropical and sub-tropical areas. (Images: Rocella lichen growing on cliff faces)

The primary colorant compound responsible for the brilliant purple color is orcein. The colorless precursor orcinol is extracted from the lichen and converted via ammonia and oxygenation into the purple orcein. Traditionally, this was extracted with urine derived ammonia and sometimes with the addition of slaked lime. If the conversion is carried out in the presence of potassium carbonate, calcium hydroxide, and calcium sulfate (potash, slaked lime, or gypsum in traditional ), the result is more complex and strongly pH sensitive litmus (Beecken et al., 2003). This is the original chemical used in litmus paper to identify the pH of solutions and is where the paper gets its name. (Image: Wool skeins dyed with lichen dyes)

A lichen is mentioned by Pliny the Elder as a ground for Tyrian purple (Forbes, 1956). This lichen, he calls phycos thalassium, grew on the coasts of the eastern Mediterranean, and the Cretian Lichens were especially commended. The original Mediterranean source of Orchil is said to have derived from Tyre from _Roccella tinctoria_ and other rock lichens in Roccella. These related colors are called conchoid purples from the influence of Tyrian purple (Kok, 1966). In the East, a red-purple robe was excavated from China dating to 2000 BCE possibly containing Orchil (Barber 1999). This predates murex (tyrian) dyeing in Crete and the Orchil dyeing in Tyre. Orchil is mentioned in the Papyrus Holmiensis in the 3rd century CE as well as by Rosetti in 1548 as a dupe for Tyrian. 

From Rosetti, Orchil was said to have disappeared around the 4th century and reappeared in the 16th century by his research. His rediscovered process consisted of pulverizing the lichen and adding it to ammoniated urine and slaked lime then waiting the required time (weeks to months) (Perkins, 1986). However, there is evidence that the process did not die out as previously thought. Orcein containing lichens similar to Rocella were used in North Europe in Denmark and Greenland during the Bronze and Iron ages from burial evidence (Casselman, 2001). These northern ammonia lichen dyes are not Rocella, but are similar varieties Ochrolechia, Lasallia, and Umbilicaria that also produce orcein. (Image: various lichens)

In the 1700's, the Swedish biologist and physician Carl Linnaeus describes a beautiful red dye can be prepared from Gyrophora Lichen. 

There are many other British lichens that produce similar colors to Orchil using the ammonia method. Large quantities of a similar dye called Cudbear (generally Lecanora tartarea and Urceolaria calcarea) were produced from the Shetlands and West Highlands of Scotland. Other lichens that produce similar compounds using the ammonia method are Evernia prunastri, Lecanora pallescens, Umbilicaria vellea, U. pustulata, Parmelia perlata. These lichens used to be used substantially throughout the British and Irish Isles, but this process has nearly disappeared. Due to extremely slow growth, difficult growing conditions, limited lightfastness, and poor commercial value, these lichens are rarely commercially grown. (Image: Cudbear growing on rock face)

Orchil Dyeing Methods

The lichen of choice (or multiple together) is first crushed, ground, or shredded into fine pieces and submerged in a solution of equal parts ammonia and water. The lichen is then left in a warm area away from sunlight and is  stirred multiple times daily to introduce oxygen. After a period of days or weeks the solution should turn a deep reddish purple and can be tested with a small amount of wool to see the color achieved. If the ammonia soak goes on too long the color can be ruined and turn ruddy. (Image: Lichens soaking in ammonia)

Adjusting the pH achieves different shades from purple to blue to red (Kok, 1966). After the ammoniafication, the dye is brought to a near boil and wool added below boiling for the most vibrant colors. Silk and other animal fibers can be dyed similarly. No mordant is required unlike most other natural dyes, though modifiers can be added to change the color. The dye is only suitable for protein fibers and involves boiling in neutral or light acidic solution. It is most commonly used as an overdye with dyes such as indigo or madder to achieve various purples and violets. (Image: Orchil dye and its dyed yarn)

Ethics

Lichen dyeing is a method fraught with controversy. Incorrect harvesting of lichen can be very damaging to their population and can cause extreme environmental damage. Farmed lichen using ethical sources is generally preferred to wild foraged lichen at least when done improperly. Dead lichen from windfall or the parts of lichen that are no longer alive or attached to their substrate can be harvested without much issue, however, it is very important not to over-harvest or collect (poach) living specimens as their populations are very sensitive and extremely harmed by climate change and ecosystem collapse. This being said, lichen dyeing is an extremely important cultural practice that is thousands of years old. The process can be practiced sustainably and non-exploitatively and it is important to learn how to do so before going about lichen dyeing or lichen collection.

Sources and further reading:

Beecken, H; E-M Gottschalk; U v Gizycki; et al. (2003). "Orcein and litmus". _Biotechnic & Histochemistry_. **78** (6): 289–302.

Bessette, A. R., and A. E. Bessette. 2001. _The Rainbow Beneath My Feet: A Mushroom Dyer’s Field Guide_. Syracuse, NY: Syracuse University Press. 

Bolton, E. M. 1991. _Lichens for Vegetable Dyeing_. McMinnville, Oregon: Robin & Russ Handweavers.

Brodo, I. M., S. D. Sharnoff, and S. Sharnoff. 2001. _Lichens of North America_. New Haven, Connecticut: Yale University Press. 

Casselman, K. D. 2001. _Lichen Dyes: The New Source Book_. Mineola, New York: Dover.

Kok, Annette. 1966. A Short History of the Orchil Dyes. _The Lichenologist_ 3: 248–272.

Perkins, P. 1986. Ecology, beauty, profits: Trade in lichen-based dyestuffs through Western history. _Journal of the Society of Dyers and Colourists_ 102: 221–227.

Beecken, H., E-M. Gottschalk, U. von Gizycki, et al. 2003. Orcein and litmus. _Biotechnic & Histochemistry_ 78(6): 289–302.

Mycopigments. “Lichen Dyes.” Accessed April 2025. [https://www.mycopigments.com/blogs/news/lichen-dyes]

Mushroom Color Atlas. “Process.” Accessed April 2025. [https://mushroomcoloratlas.com/process/]

Cornell Mushroom Blog. “Dyeing with Lichens & Mushrooms.” Cornell University. December 12, 2006. [https://blog.mycology.cornell.edu/2006/12/12/dyeing-with-lichens-mushrooms/]