How many times have we been enchanted by the beauty of some items in leather, tanned by artisans and put on sale in the small shops of our cities of art? The leather, made from the processing of animal leather, is one of the largest evergreen fashion. But how do you work? And, above all, what is the difference between leather and leather, if both come from the same raw material? In this article, we try to discover together the characteristics, history and workmanship of leather.
Take a day, in spring, a nice walk through the streets of Florence. Many small shops, one behind the other, exhibit their leather workings. Bags, belts, jackets, shoes. There’s all sorts of things. Then we stop to look, to touch with our hands that hard material, made smooth or rough depending on the wise hands that worked it – or tanned – to make it what it is. We feel the unmistakable smell of new and ancient at the same time, the smell of a tradition that for millennia is mastered without delay and without perplexity.
This is the processing of leather, a historic processing that still maintains its artisanal traits and that has made some of our cities – such as Florence, in fact – famous throughout the world. Are you curious to know how leather is worked and what are all the steps? Follow me in reading this article and you will all be much clearer, I promise!
Leather or leather? Let’s be clear!
Before proceeding, it is good to clarify the terminology. Very often we have asked ourselves “but is it leather or leather?” or “what is the difference?” , and just as often this question has fallen into oblivion. Well, here is the mystery revealed: between the terms leather and leather there is no difference!
Strange as it may sound, it is so. There is no difference. It is the same product that we simply tend to call differently depending on the uses that are made of it. Usually, in fact, we recognize in the term leather something more hard or more smooth and almost always a color brown…leather, that’s right!
We are therefore led to define leather soles of shoes, belts and even some bags, but we would hardly say leather jacket or leather bag, items for which we continue to prefer the term leather.
Before tanning, preservation
Before proceeding with the tanning, it is necessary to better preserve the skin in order to make it more workable. There are several preservation methods but the main ones are salting and drying.
The salting consists in salting the skin with some common salt, thus making to remove any remaining liquids, and is suitable for thicker skins such as beef. This method is highly economical and easy to apply, but has as its only problem the final release of excessive quantities of salt that risk contaminating the waters of the receiving bodies into which the waste is poured.
The drying process, however, consists of a mechanical drying that does not produce pollution but is suitable only for very thin skins, such as sheep and goats.
The phases of tanning
The tanning process is an articulated process that takes place in different phases, which is reached after preparing the leather through the phases of rinverdimento, scarnatura, depilation, calcination, splitting, descaling, maceration and degreasing. The purpose of all these phases is to obtain an easy to work product, however still possible of rot.
Tanning is, instead, the process that transforms the still putrescible material into a non-putrescible and consequently more lasting material. It is a chemical process that is carried out through tanning agents that react with the skin.
The most common method is the one in which chromium is used, with which it is estimated that almost 90% of the existing leather products are produced. It is a rather inexpensive and fast method that ultimately produces a skin of color green-blue, also called em>wet-blue.
The other method, the oldest, is tanning with vegetable tannins, and was the most used method until the nineteenth century but much more complex articulated, so generally the method is preferred to chromium.
After tanning, finally, the leather undergoes a series of further treatments that make it flexible and ready to create articles. The post-tanning phases can be summarized in: wind, shaving, splitting, reconditioning, dyeing, fattening, wind-up, drying and finishing. At the end of all these steps, finally, the leather is ready to be sold or to create wonderful handmade pieces.
Cover Image: stamperiamast