About Hide Tanning

What is hide tanning?

Hide tanning is the act of turning animal skin into textile.

Textiles are one of the oldest technologies of humanity.  Animal-derived textiles predate plant-based textiles by many thousands of years.  Alongside hunting and toolmaking, hide tanning has co-evolved with human community.

Natural hide tanning uses simple, organic ingredients found in a local ecosystem.  Unlike modern “chem-tanning,” which relies on chromium and other toxins to produce leather, natural hide tanning is safe and sustainable.

There are three categories of natural hide tanning: Smoke-tanning, also called brain-tanning; Bark-tanning; and Mineral tanning. Additionally, the wonderful quasi-textile Rawhide can be considered a fourth category in its own right.

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Smoke-tanning (Braintanning)

This is the oldest method of hiding tanning, and therefore the oldest textile in the world!  It is also the only hide tanning method found around the globe, in every corner of the world. This is likely because it is made with the simplest ingredients found in any ecosystem.

Smoke-tanning makes a beautiful, lightweight textile similar to linen called buckskin (or, chamois) and it can be used to make fur-on rugs, thick, sturdy purses and packs, and many textiles in between.  Since it can’t be reproduced in a factory setting, smoke-tanning always happens on the home and community level.

This method is defined by the ingredients of fat and smoke combining to cause a molecular transformation of skin protein that transforms a kin into fabric.  The fat (in the form of, yes, brains) absorbs into the hide to lubricate the skin fibres, while the smoke organically reacts with the fat molecule.. A hide is worked vigorously while it dries over the course of a day.  It is stretched with tools and by hand to turn it from a stiff piece of rawhide into a smooth cloth that is softer than any cotton blanket.

The smoke-tanning courses offered by Fern + Roe use European techniques, mainly in traditional Scottish methodology.  This includes a gentle alkaline “bucking solution,” which hides are soaked in for a week prior to a course.  The bucking solution denatures any scent from deer hides and prepares the hide for the tanning process.

Buckskin (chamois) is the (hair-free) velvety-soft textile made from tanning any mammal hide in the smoke-tan method. Historically in the English-speaking world, buckskin was also known as “chamois leather,” named for the mountain goat who was most valued for this type of tanning. The name buckskin comes from the bucking solution. It is not named for a male ungulate, also called a buck. The Old English word for a male deer was “hart,” and later “stag.” The modern word for a male deer might just come from the bucking solution used for buckskin, but this etymology is a bit of a mystery.

Fur textiles can also be made from the smoke-tanning process. They do not go through a bucking solution but need to have extra work done on them to get them soft, since all that hair acts as a firm structure for the hide. Hides are dry scraped to become thinner and softer this, and when thoroughly worked they can become plush rugs, blankets, or clothing.


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Bark-tanning

Over the centuries, Bark-tanning was innovated to create leather. By taking rawhide and buckskin, and mixing them with bark and plants, tanners created a new textile. This mixing act extracts the plant cell constituent, tannin (tannic acid). Tannins transform a hide into leather by reacting with the skin proteins on a microscopic level. A hide will literally turn from skin to a red leather right before a tanner’s eyes. Bark-tanned leather became the foundational craft needed for weaving, by providing structure for looms, and many other folk crafts. It also became the preferred tanning method in the urban English world over the past 5 centuries, so much of the historical record speaks to leather production, leather guilds, and bark-tanning influence on other folk crafts.

Bark-tanned leather gets us sturdy objects like bags, saddles, belts, and hiking shoes. Natural leather can also be made into a soft fabric, similar to buckskin (chamois) but with greater water resistance.  Bark-tanning can also be used to make fur-on rugs, and these have the highest durability and water resistance of any naturally tanned leather.


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Mineral Tanning

Mineral Tanning also creates leather, but through a different ingredient list. It utilizes the mineral alum (aluminum potassium sulphate) to create a bright-white leather, and when mixed with other minerals new textures, colours, and depths can emerge. Alum is also used in naturally dyeing as a mordent, and this make alum-tawed leathers perfect for making bright, colourful textiles.

While Smoke-tanning and Bark-tanning are worldwide hide tanning practices – due to the presence of fat, smoke, and plants globally – Mineral tanning is denizen to specific geographies where alum and other minerals are found in high concentration in the soil. This includes Eastern Europe, SWANA, and South Asia. Mineral Tanning is also found where minerals form encrustments (outcroppings), which tends to be dry climates but is even found in northern Scotland. Its practice evolved with the evolution of sheep tending and it is currently used mainly for fur-on leathers, though its smooth white leather had a major impact on the historical Silk Road trade route.


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Rawhide

Simply put, Rawhide is a dried hide. There is more to this story, though. Skin acts like a textile once it has been dried, so Rawhide can be used in a variety of ways to construct a product of object of desire. It can be taken when wet to form a particular shape, or dried flat and then cut out. Rawhide has been made into anything from containers to horse bridles to shoes to windows. Most famously, it is the textile placed on drum heads, to give them their deep and expansive resonance. Rawhide is the original cast material used to set bones, applied with the principle of using it when wet to form it into the shape one wants. It is a natural canvas and can be made into a bright white backdrop for painting.

Academic research into historical and natural hide tanning is limited, but we’ve curated a small collection here and will continue to grow it.  

Sometimes the science behind these articles is a little off.  For example, it’s common to see the word “cure” in the literature which does not signify anything, and often there is a mistaken understanding that smoke and fat do not transform the molecules in a hide.  These misunderstandings likely arise because academics are not necessarily hide tanners nor chemists.  So, take what makes sense to you and leave the rest.  If you’re unfamiliar with the fundamentals of hide tanning, look to the descriptions of natural hide tanning above.

 Resources

Fish and Chaps: Some Ethnoarchaeological:

Thoughts on Fish Skin Use in European Prehistory Essay from Open Archeology in 2020

On Tanning Leather.--
Preparation of Hides.

Article from Scientific American in 1850

Products of animal skin from Antiquity to the Medieval Period

Manuscript compiled in 2016 by German academics focusing on European Medieval period

Rural tanning techniques

A research project undertaken in 1960 by the UN Department of Food and and Agriculture

 

 

Skin processing technology in Eurasian Reindeer cultures

A PHD thesis from Oslo University in 2007

Vegetable Tanning Agent

An overview of the chemistry behind bark tanning, not written for hide tanning but applicable!

Women’s Work: Skin Processing in Northern Hunter

Gatherer Settlements and the Archaeological Context

Archaeological Invisibility and Forgotten Knowledge

This comprises Chapter 15 of the academic publication Archeological Invisibility and Forgotten Knowledge, from a Polish university in 2007