Co-Geeking

This post is a part of our Making Clothes series.

Leather is produced from a wide variety of different animal skins, from both wild and domesticated creatures.

Origins of Leather Production

It’s unclear when humans started wearing clothes—and what, precisely, can be identified as clothes in archaeological finds—but the first garments were likely some forms of hide or leather wrappings. Tools for scraping hides date back at least to 120,000 BCE, probably already some hundreds of thousands of years earlier, while studies based on body lice suggest clothing might have been adopted around 170,000 BCE.

The oldest archaeological remnants to do with sewn apparel are bone awls and needles, the oldest of which date back to roughly 80,000 BCE. Using them as evidence, it has been estimated that the earliest clothes made from animal skins were produced approximately 70,000-30,000 years ago, but the question is still open.

However, a recently published study of small sandal-like prints, found in sandstone at three places along South Africa’s Cape coast, discussed not just the sandal prints, but also indications of strap attachment points within the prints. None of the three sites have been dated yet, although nearby sites suggest that they may be from around 70,000 to 130,000 BCE. If confirmed, that’s a staggeringly long time for humans to have been constructing multi-part coverings for themselves.

The oldest extant shoe we do know of (the so-called Areni-1 shoe) was found in Armenia and dates back to the local Copper Age, 3600-3500 BCE. It was made of leather and various grasses. The footwear Ötzi wore, from 3300 BCE or so, involves similar materials: a leather covering over sock-like inners made of lime or linden bast. He also wore two coats, a belt, leggings, a loincloth, and a cap, all carefully sewn from leather or skins of various kinds.

Bog deposits can preserve details that don’t survive in regular burials. For example, the 2nd century BCE Huldremose woman from Denmark had a cape made from several dark brown sheep skins. This outer cape had a collar of light-colored sheep skin, and the wool side was turned out. Underneath she wore another cape, made from 11 small dark lamb skins with the wool side in.

Types of Leather

Domesticated mammals like cattle, sheep, goat, and pig yield most modern leather, although leather can also come from wild animals such as deer, squirrel, and rabbit, as well as non-mammals like ostriches, lizards, and fish.

There is quite a variety of vocabulary connected with leather, starting with the types of raw material. Pelts are typically undressed and still contain the hair, fur, or wool. The word hide is used of pelts from larger animals (cattle, moose, etc.), while those from smaller animals (rabbits, pigs) are sometimes referred to as skins. Fur, when speaking of materials, refers to a processed hide with the hair retained. Treated hides or skins without fur or hair are leather proper, but you do also see the word leather as a generic term for any kind of animal skin product.

These days, tanneries buy quality-graded raw hides. Issues like holes, deep cuts, scars, large abrasions, discolorations, skinning machine damage, remaining hair, and grain inconsistencies affect the grading. Grades are numbered from one to three (best to weakest quality), in addition to which there is hide considered untannable.

The quality and characteristics of leather vary based on where in the hide it comes from. The shoulders generally have a firm yet malleable and flexible feel. The rump areas are the thickest and firmest in a hide and make good sturdier items such as heavy belts. The areas ranging from the spine towards the belly are some of the best leather available in a hide, while belly leather is a little softer and stretchier than others.

Like human skin, animal skin is composed of layers. In modern production, leather is usually split to gain materials with different qualities, most commonly into outermost layers (yielding e.g. full grain, top grain, corrected, or nubuck leather) and lower layers (e.g. split leather, suede). Both kinds can be treated further.

The treatment can also give a leather its name. For instance, while both have a nap-like soft finish, nubuck is considered top grain and suede a split. Chamois is a soft pliant leather produced from the skin of the chamois (a species of mountain goat) or from sheepskin. Patent leather has a high-gloss coating and was developed in the 1700s.

Collecting Materials

The only way to get leather is to skin something. Skinning is recommended as soon as possible after death (because otherwise the hide will start decomposing in a matter of hours and because it makes the following steps easier). Smaller animals (e.g. squirrels, minks) can also be skinned as a tube.

The amount of leather that comes from one animal naturally depends on the size of the animal and the condition of its hide. In modern leather processing, a typical cow hide yields 4.6 square meters of finished leather, while a sheep hide yields 0.8 square meters. Hides in poor condition may have to be trimmed to be usable.

Skinning is relatively quick, but it is only the first step in leather production. The preparation, preservation, and treating the hide takes many more steps that may amount to months of labor before the leather is ready to be cut, fitted, and finished.

Processing Leather into Useable Forms

The core of leather processing is called tanning. Tanned material is flexible and doesn’t rot. During tanning, the protein structure of a pelt is chemically altered to protect it against moisture and microorganisms. It basically means the replacement of natural fluids and fats with preservative agents (minerals, tannic acids, and fats or oils).

There’s an enormous variety of traditional tanning methods, so the description below is bound to be cursory.

Prior to tanning, the fresh raw skin (green hide) needs to be prepared. It involves fleshing (removal of meat and fat by scraping or pounding) plus dehairing if desired (soaking in water, urine, or an alkaline solution), then the hide is stretched over a frame and dried.

Raw hides dry out hard and inflexible, and they can also putrefy if they get wet again. Green hides can be cured to prolong the time they can be effectively treated in. It often involves salting (or, in modern processing, applying other chemicals) to remove excess water. (Compare this to curing meat with salt to preserve it.)

There are many other options for pretreatment, for example liming and deliming (a chemical process to remove epidermis, hair roots, undesired fats, and soluble protein), bleaching, and pickling and depickling (altering the pH value).

So-called vegetable tanned leather is treated with tannins from plants. Tree bark or leaves are an old, convenient source for tannic acids. Tannin baths derived from different barks produce different coloring on the leather (e.g. birch yields a yellowish and spruce a darker brown).

Impregnating leather with various fatty or oily solutions (fatting, fat curing, fat liquoring) for preservation and waterproofing is an age-old option. It has the benefit of softening the leather as well.

Smoking or smoke tanning is another possible processing method. Formaldehyde from the smoke offers some microbial and water resistance. For instance, fat cured and smoked chamois leather (made by oil tanning where fish oil or other fatty substances are pounded in until they have replaced the original moisture) can be washed and wrung almost entirely dry.

If desired, some finishing processes like buffing, waxing, or embossing can be applied. Dyeing leather is possible during or after tanning. Some methods or colors are more difficult to achieve, others easier. For example, vegetable tanned leather can be dyed black even at home simply with vinegar and rust. Henna-dyed leathers apparently tolerate rubbing quite well, while their lightfastness is only moderate.

As the processing times of various methods vary so widely, it’s extremely difficult to estimate the time devoted to tanning in the past. Early periods presumably largely favored simpler approaches, like a mostly mechanical treatment (working the animal’s own natural fats or brains into the skin) plus smoking. It’s probably fair to estimate from a few days to a week even for this method of tanning.

Alternatively, tanning leather thoroughly in a tannin bath can take months. Due to the extensive time commitment, in later Iron Age Finland vegetable tanning was likely used for a handful of days only (essentially to dye the leather), and the tanning process was finished with a fat treatment.

Typical Uses of Leather in Clothing

Leather garments are durable, nearly waterproof, and pragmatic for many demanding tasks. Footwear is an obvious choice due to the durability of leather: boots, shoes, moccasins, and slippers, sometimes lined with felt or with fur inside, are still being made. (Armor is another, but that’s beyond our focus here.)

Different furs and leathers are suited to and have historically been used for different purposes. Moreover, even though leather, hide, and fur might have been sourced from the same animal, the uses that those materials have been put to often differ both in prehistory and historical eras. Leather was and still is used for clothing meant to endure harder wear, while fur is reserved for warmth and a show of luxury.

As an example, from around 1800 BCE onwards, the residents at the various sites around the Tarim basin in Xinjiang, northwestern China, wore a variety of leather garments: footwear (some of them dyed), skirts with the fur turned inside, sheepskin trousers, leather coats (e.g. of sheepskin), and mittens (or possibly a falconer’s glove or the like). An interesting coat variant from the Qizilchoqa cemetery, approx. 800-530 BCE, had the fur turned inside with integrated gloves (i.e., sleeves continuing as mittens).

In the Nordic countries during the Iron Age, sturdy goat leather was often used for footwear, or if fur was desired, seal, deer, moose, or cow hides were selected, especially from around the legs. Thicker cow or calf leather was picked for belts and shoe soles. Soft, thin chamois was made from deer or goat, and thicker types from moose. Fur clothes were made from summer deer, fall reindeer, or sheep pelts, all of which might also be dehaired and used as leather for shirts, pants, or hoods.

Fat-treated leather garments tolerate wet conditions well. For Nordic Iron Age sailing crews, the layers closest to skin were probably wool, since it stays warm even when wet, but the outer layers may have been made from vegetable tanned goat or sheep leather and fatted leather. By processing a hide with a mixture of tallow and tar it’s possible to get it nearly waterproof.

During historical periods leather was also used for gaiters, headwear, and fur leggings, for example. Other garments commonly made from leather include cloaks or capes, while fur has long been used as lining or trimming for woven cloaks or coats. For instance, the high-status 900s CE man from Bjerringhøj, Denmark, wore a cloak of beaver skin decorated with tablet-woven bands of wool, and a woman from Hvilehøj, Denmark (also from 900s CE), had a fur cape as well. Hers was made of forest marten edged with beaver skin and various bands of wool and silk. She also wore shoes of fine goatskin with hair on the outside.

A traditional Sami beaska (in Finnish peski, a kind of an anorak) requires about 5-7 reindeer skins to make. In the coldest season, the Sami sometimes wore two beaskas, the one closest to the body with fur facing in and the outer one with fur facing out.

Also utility products out of leather have long been common. For millenia, leathers, hides, or furs were used to wrap bodies in for burial or placed underneath a body in a grave. Other examples include tents and other shelters, cushions, drum skins, saddles and reins, scabbards, sheaths, fur or leather belts and belt pouches, and bags of various kinds. There are finds from Iron Age Finland where fur was used even to line knife sheaths.

These days, lamb and deerskin are chosen for soft leather in more expensive uses, and deerskin for work gloves and indoor shoes. It should be noted that fluctuations in heat and humidity can ruin a leather garment. They should not be exposed to high heat, and it’s recommended to spread them out to dry for best longevity.

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