The Curing of Hides and Skins in European Prehistory
Groenman-Van, Waateringe W., Kilian, M., Van Londen, H., Antiquity
Like all organic materials, prehistoric hides and skins are preserved only under specific circumstances, in our area mostly in anaerobic environments.(1) Thus there are numerous examples of leather and fur found in waterlogged conditions from the Roman period onwards.
However, prehistoric leather finds are extremely scarce. Until the find in 1991 of the man from the Hauslabjoch (the Iceman) in northern Italy (Hopfel et al. 1992) with all his frozen equipment, only two leather (or fur) finds were known from the European Neolithic, both from peat bogs: a sheath of a flint dagger from Wiepenkathen near Stade, Germany (Forbes 1966: figure 1) and a fur poncho from Denmark (Hald 1980: 56, no 31), the latter dated palynologically.
Bronze and Iron Age fur and leather finds are known from peat bogs, for example in Denmark (Hald 1980), Germany (Dieck 1965) and the Netherlands (Groenman-van Waateringe 1970; 1990), from oak-log coffins (Hald 1972) or salt mines such as Hallstatt (Piggott 1965: plate XXVII; Barth 1992a; 1992b).
These leather finds have only been preserved by a secondary tanning process, such as caused by the acid milieu in peat bogs and the salty environment of the mines in the Austrian Alps (Salzkammergut). The preservation in oak-log coffins of tiny pieces of leather falls into the same category, since oak provides a very good tanning medium. Thus these finds cannot be used to identify the original tanning process.
The earliest prehistoric leather find from a waterlogged deposit is a bag from the late Iron Age site of La Tene in Switzerland (Forbes 1966: 16).
If we assume the use of leather clothing by the Iceman to be characteristic of the Neolithic (cf. Winiger 1995), how can we explain the lack of such finds from waterlogged deposits with otherwise excellent preservation of organic material?(2)
In an attempt to get more information about the environment of the Iceman and of the animals whose hides were used for his clothing, some loose animal hairs of his equipment were prepared for pollen analysis. The results were remarkable (Groenman-van Waateringe 1993). The pollen grains in the sample could be divided into two categories: pollen with normal size and normal colour, and pollen approximately half the normal size and pale in colour (FIGURE 1). These latter pollen grains comprised 44% of the total. The two pollen categories have been explained as being first, the pollen blown into the hide when man was wearing it as clothing (the pollen of normal size and colour); and second, the pollen blown into the hide when the animal was still roaming through the woods, i.e. the small and pale pollen. It was assumed that the size and other qualities of this latter pollen had been affected by some kind of preparation of the hide (Groenman-van Waateringe 1995).
[Figure 1 ILLUSTRATION OMITTED]
Technique of curing hides and skins
Hides and skins are treated to arrest their ultimate decay through salting, drying or tanning. Tanning will chemically change the pelt to render it resistant to water and decomposition. Several tanning methods are known, either as vegetable tanning, mineral, oil and aldehyde tannage (which is the modern equivalent of the ancient smoke tanning (Forbes 1966: 5)) or as a combination of these. The changes brought about by vegetable and mineral tanning are irreversible, whereas smoke-tanning is not.
In Roman and Medieval times vegetable tanning was the rule (cf. Groenman-van Waateringe 1967: 19-21; 1984: 15-17). This technique was apparently not used until the late Iron Age.
In the find from the Hauslabjoch, which consists of a variety of animal hides, skins and calf leather (Groenman-van Waateringe 1993), we have, for the first time, the possibility of establishing the prehistoric curing methods without any secondary influence. A preliminary investigation of the Hauslabjoch material at the Westdeutsche Gerbereischule in Reutlingen, Germany, has not yet provided unambiguous evidence for the curing process used. …