Leather can be made in a number of ways. Generally this is begun by de-fleshing the skin or hide, and de-hairing (although leather can be made with the leather still intact).
- The easiest is to simply let the skin dry into rawhide, sometimes called green hide.
- The second method is oil or fat curing (this is sometimes called "oil tannage" or chamoising - both terms are inaccurate as no tannage actually occurs, and chamois specifically refers to the oil tannage of a particular type of goatskin). Massaging oils and fats into the skin or hide helps to oxidize the oils and in this way cures the leather.
- The third method is to apply various minerals and/or salts to the green hide, which cures the hide and acts as a preservative.
- Alum tawing is an ancient and period practice that creates white leather that may be dyed.
- Chromium Tanned or Chrome Tanned leather is cured by using various chromium salts. It is not a period practice, and there is no "tannage" involved. This found in leather shops and is identifiable by the leather being coloured on both sides. It also can be dyed very bright colours.
- Parchment is made by lightly curing a thin green skin with any of a variety of materials including chalk.
- Salting - this is simply taking the hide or skin or hide and liberally applying salt and letting it dry.
- The fourth method is to smoke the hide (aldehyde tannage), which can frequently involve massaging oils and fats into the leather as well to keep it supple. When animal brains are used to massage into the leather this is called "brain tannage". Recent studies have shown that the wood smoke releases aldehydes and phenols into the leather, chemically altering the hide into real leather - and therefore "tanning" the leather.
- The fifth method is vegetable tanning in which the skin or hide is immersed in tannins and these are allowed to soak through the material until the hide changes. There are several types of vegetable tanned leathers to consider.
- The first of these is plain vegetable tanned leather - this is what you will get from a standard leather supplier. It is made in a modern fashion, using modern chemicals, techniques and so on. These are made very quickly, in a matter of weeks) and have slightly different properties than historically tanned leathers - however, for most SCA purposes it serves quite well.
- Pseudo-tannages is a term used to describe leathers that were not fully tanned, tanned in a controlled method (e.g. Bog bodies), and arguably modern vegetable tanned leather.
- Pit tanned leather is what was used in the Middle Ages (and in fact up to the early 20th century). There are distinctions in sub-varieties of pit tannage, but the most common type of pit tannage used a sequence of various liquors made from leeched oak barks, of differing ages and strengths. The hide was soaked in these in a process that could take 6 to 12 months. You can still get oak bark, pit tanned leather, but it's extremely expensive.
Uses of Leather
- Leatherworking in the Middle Ages - http://www.personal.utulsa.edu/~marc-carlson/leather/leath.html
- Medieval Leatherworking list on Yahoogroups - http://groups.yahoo.com/group/medieval-leather/
- Stefan's Florilegium's article on leather - http://www.florilegium.org/files/CRAFTS/leather-msg.html
- Atlantian A&S Links - http://moas.atlantia.sca.org/wsnlinks/index.php?action=displaycat&catid=41