September 14th, 2018
About The Leather We Use
In an earlier article, we wrote about leather and why it’s such a good material for shoemaking. It covered the history of leather, from prehistoric times when early man used animal skins to make basic clothing, through to the modern leather industry of today.
Here we look at the different types of leather that are available for shoemaking, consider the various features, advantages and disadvantages of each and explain some of the terminology that’s used to describe them.
What is real leather?
Leather can be made from the tanned skins of many different animals. The most common are cattle, goats, sheep and pigs, but it can also be made from antelopes, camels, snakes and lizards, crocodiles, ostrich, seals, sharks, etc.
If the finished leather has a surface coating which is more than 0.15mm thick or which is more than 30% of the overall thickness, then it should not be described as genuine leather, but as ‘coated leather’. If the tanned hide is broken up into fibrous particles, and reformed into sheets with a binding agent, then it should be called ‘bonded leather’. Neither of these are suitable for high-grade footwear.
Sheepskin is often used for clothing leather as it has a soft feel and is comfortable to wear. It is very good for lightweight moccasins and slippers, but doesn’t have enough tensile strength for shoes of heavier constructions.
Pigskin is plentiful and relatively cheap, but it does not have a fine grain structure and tends to look a little coarse.
Bovine leather (i.e. from cattle) tends to be the most popular for shoemaking and it blends fine appearance with strength and durability. Calf skins are usually best for the finest footwear as they are softer and have a tighter grain structure than the bigger skins of older animals.
It is generally recognised that European countries such as Italy, France and Spain have the best climate, pasture and farming methods for breeding the best cattle and therefore produce the best skins. Although there are large quantities of leather produced in other areas of the world, much of it is not of good enough quality for high-grade shoemaking.
Shoe upper leather
Most shoe upper leather is chrome-tanned – a process that gives it the water-resistance, durability and suppleness needed to withstand the constant flexing that occurs when we walk.
Shoe lining leather
Our lining leathers are usually taken from kips, which are young cattle from India. These hides are soft and therefore very comfortable and suitable for using inside the shoe where they are near the foot.
The best lining leather is vegetable tanned, or semi-chrome (with a higher vegetable content than chrome-tanned), which makes it more porous and allows it to absorb natural perspiration during the day and then disperse it again when the shoes are taken off.
Shoe soling leather
Good quality soling leather comes mainly from Europe and the Americas, and is vegetable tanned. This produces a lovely plump, round feel which is resistant to abrasion. The leather is compressed to compact the fibres and increase its wearing properties.
The leather industry is beset with mystery and myth and, when it comes to identifying the various types of leather you cannot beat proper training and experience. But, with a little knowledge, care and patience, anyone can do it. Ask yourself how it feels. Aside from appearance, how the leather feels and handles is a big clue to its type. ‘Aniline’, full-grain leathers feel like real skin – supple and flexible, whilst a heavily pigmented (or protected) leather can feel rather like plastic. Leather upholstery in cars is almost exclusively pigmented to protect it from years of heavy use, as is most domestic upholstery leather. One of the current challenges facing the leather industry is to produce lighter, aniline-type leathers that have the durability and resistance to soiling that pigmented leathers have.
Here is a mini glossary of some terms that you may have come across and wondered what they mean:
Full grain – the grain surface is left intact before applying the finish, so the hair follicles can usually be seen. This type of leather requires a little more care than corrected-grain, but it will reward you in the long term. When the shoes are flexed, any creases that occur in the leather tend to ‘recover’ and, if looked after, this type of leather can be incredibly long-lasting. It moulds to the shape of your feet and provides the best level of comfort.
Corrected grain – sometimes called ‘polished’ or ‘smooth’ leather. The grain surface is sanded or buffed to remove imperfections before the finish is applied. This type of leather usually has a shiny, smooth finish. It looks smart and, because of its smooth surface, is relatively easy to clean. However, it tends to be a little firmer in feel and is perhaps less kind to the feet than a full-grain calf leather. Another characteristic is that, when the shoes are flexed in wear, the creases tend to remain in the shoes and after heavy wear, the finish can start to crack.
Suede – this type of leather is made, either by abrading and dressing the flesh side of the leather (as opposed to the grain side) to create a velvety ‘nap’, or by dressing a split (the middle or lower section of a hide).
Pull-up leather – sometimes called ‘waxy’ or ‘oily pull-up’. This is usually a full-grain leather that lightens in colour when stretched during lasting or wear to produce a two-tone or worn-in effect with time.
Nubuck – aniline dyed leather which has been lightly abraded on the grain surface to create a velvety finish or nap. In some cases the grain pattern is still visible. The nap is very fine because of the tight fibre structure in the grain layer.
Embossing – a process that heat presses a ‘grain’ pattern into the leather. If not sanded or buffed, these leathers are still considered to be full grain. Embossing produces a much more consistent pattern than the more natural methods of ‘tumbling’ the leather in a drum or shrinking it to obtain the ‘grain’ look.
Aniline – actually, there’s no such thing as aniline leather these days. ‘Aniline’ is a chemical that, in days gone by, was used in the dying process, but it was found to be carcinogenic and was banned. So nowadays the term is used to describe a leather that is dyed rather than pigmented and has a more natural appearance.
Pigmented Leather – perhaps the most durable and used in the majority of furniture upholstery and almost all car upholstery. The durability is provided by a polymer surface coating which contains pigments. The surface coating allows the manufacturer more control over the properties of the leather, e.g. resistance to scuffing or fading, but it will also lack some of the desirable properties of full-grain leather. And, if the thickness of the coating is more than 0.15mm, then the product can’t be sold as leather.
Finished split – the lower layer of the hide, below the top or grain. You need to find a cut or torn edge to distinguish a finished split from full grain or corrected grain pigmented leather. In a full-grain leather, the fibres are much more tightly packed near the grain surface, while in a finished split (lower layer of the skin) the fibres are equally loosely packed all the way to the pigment coating. The lack of a grain layer will also be apparent if a finished split is torn.
We all fall for sales talk at some time. But, when you buy a leather item you expect quality, comfort and durability… and you expect it to be leather too! It’s reassuring to know that, when you buy a pair of English Goodyear welted shoes, they’re likely to have been made from some of the finest leather produced anywhere in the world.