A Guide to Leather

Beginning in the early Stone Age people have prepared the skins of the animals they hunted for food through processes of smoking, sun-drying or salting them to produce footwear, shelter and clothing. Although the finished material, known as rawhide, is relatively durable it's also stiff and subject to decomposition.

To soften and better preserve the hides a process of soaking them in natural plant tannins, or “tanning”, was eventually developed. While there is no record of the actual discovery of the tanning process, the earliest evidence comes from Mehrgarh in current day Pakistan between 7000 BC and 2000 BC, and from Sumer around 3000 BC.

The hides of mammals are composed of three layers; a thin outer layer known as the epidermis; a thicker central layer, the dermis; and a subcutaneous fatty layer. The dermis layer is used for leather. A fresh hide contains about 65% water and 35% protein; mostly collagen, a fibrous protein held together by chemical bonds. Tanning is the science of using chemicals, enzymes, and tannins to dissolve excess fats and nonfibrous proteins and strengthen the bonds between the collagen fibers.

As in ancient times, the hides used today are a by-product of animals raised for the meat, dairy and wool industries.
No animals are killed exclusively for use as leather.
We are dedicated to providing ecologically sustainable products.

Roughly half of all leather produced today is used to make shoes, and about 35% for clothing, accessories and commercial products. An additional 15% is used by the upholstery industry.

Vegetable Tanning

Until the 19th century most tanning was done by the vegetable process using the bark of trees such as oak, mimosa, and hemlock which contain a phenolic compound known as tannin. These tannins bind to the collagen proteins in the hide, coating them so that they become more resistant to water and bacterial agents. The process also makes the skin softer, stronger and more flexible while producing the traditional scent generally associated with premium leather goods.

Vegetable tanning is the most environmentally-friendly method of leather production. While this method of tanning does use quantities of water, the waste can be efficiently recycled without toxic residue. It does not pollute the environment the way the chromium-based leather tanning process does. There is also less machinery, and so less electricity, involved with the vegetable tanning process.

The disadvantage of vegetable tanning is primarily in the time (usually months or even years) and traditional skills required to produce the finished hides, which is reflected in their cost. Vegetable tanned hides are uniquely suitable for artisanal tooling and carving.

Almost all of the leather we use is premium full grain or top grain, vegetable tanned cow hide sourced from tanneries subject to E.U. regulation. 

Chromium Tanning

The chrome tanning process was invented in 1858 by the German technologist Friedrich Knapp and Hylten Cavalin from Sweden, and was patented by an American chemist, Augustus Schultz in 1880. Although the basic principle of modifying the hide’s protein structure is the same, a chromium sulphate solution is used instead of natural vegetable tannins, and the traditional vats are replaced by rotating drums which can decrease the tanning time to a single day. The chrome salts create a protective layer on the surface of the hide, making it more resistant to water and sealing in dyes and colorants. However, this also means that it cannot be carved or tooled by traditional methods.

Today, chrome tanning accounts for 95% of shoe leather production, 70% of leather upholstery production and almost 100% of leather clothing production.
Sodium dichromate, a principal raw material used in the process, is a carcinogen and causes damage to blood, kidneys, eyes, heart and lungs.
Sun drying and boiling can also oxidize and convert chromium 111 used in the tanning process into the highly toxic hexavalent chromium V1.

Because chromium tan leather has specific properties (flexibility and water resistance) that are sometimes required, we may occasionally use it in our products if sourced from tanneries that are properly regulated.

 
Rawhide

Raw hide is commonly used for drum skins, pet chews and other applications that require a tight, stiff & resilient material. It is literally a raw skin that has been cleaned, cut or molded to shape and then dried without being submitted to tanning. Bleaches and dyes are commonly added to rawhide, which is a controversial practice especially for pet owners: however they are not necessary to the process.

 

Full Grain: Full grain leather is the complete skin surface of the hide. As the skin is not sanded or polished, any scars or other textures remain so only the best quality & most aesthetic hides are chosen for full grain.
Full grain leather is the most durable, natural and strongest type of leather. In many cases it is preferred for its natural textures.

 

Top Grain: Top grain leather is uppermost surface from full grain, but the leather's surface is sanded and polished to remove any textures or blemishes and present a perfectly smooth surface. Top grain is often used for traditional tooling and carving as the prepared surface of the hide is much easier to work on and presents better qualities for burnishing and impressions.

 

Split Leather: Split leather is usually the corium, or inner layers of the hide after the skin side has been removed to make top grain leather, although it may also include top grain. Suede is typical of split leather, with both surfaces of the hide featuring the fuzzy, unpolished look of the flesh side. Suede leather is less water resistant than top grain unless specially treated, and requires brushing to maintain it's soft appearance.

 

Nubuck Leather: Nubuck leather is top grain leather that has been sanded to create a soft, velvety texture. Nubuck is wear-resistant and generally resilient against most forms of damage, but can be easily marred by scratches and is less water resistant.

 

 

Artificial leathers:
MOST "Vegan Leather", "PU Leather", "Pleather", “Naugahide” .etc are made from synthetic plastics such as polyvinyl chloride (PVC). These chemicals and their production have well documented health and environmental hazards.
We don't use them.

Plant based leathers: There are various plant materials used to simulate leather. To our knowledge they are not suitable for our products.

Bonded leather is made from scrap leather which is ground up, mixed with a binding agent, usually latex or polyurethane, and “bonded” onto a fiber sheet which is stamped with a leather grain pattern. This is commonly used as an upholstery material for inexpensive sofas and chairs as it may still be labeled as "genuine" leather.
We don't use it, either.