Birch bark tar use as an
adhesive began in the Middle
Paleolithic.
Neanderthals produced tar through dry distillation of
birch bark as early as 200,000 years ago. A 2019 study demonstrated that birch bark tar production can be a simpler, more discoverable process by directly burning birch bark under overhanging stone surfaces in open-air conditions. However, at
Königsaue (Germany), Neanderthals did not make tar with this method but rather employed a technically more demanding underground production method. A find from the Dutch North Sea and two tools from the Italian site Campitello show that Neanderthals used birch bark tar as a backing on small 'domestic' stone tools. Birch bark tar also has been used as a
disinfectant, in
leather dressing, and in medicine. A piece of 5,000-year-old
chewing gum made from birch bark tar, and still bearing tooth imprints, was found in
Kierikki, Finland. Genetic material left in the gum enabled novel research to identify population movements, types of food consumed, and types of oral bacteria found on their teeth. A different chewing gum sample, dated to 5,700 years old, was found in southern
Denmark. A complete
human genome and oral
microbiome was sequenced from chewed birch bark tar. Researchers identified that the individual who chewed the gum was a female who was closely related genetically to
hunter-gatherers from mainland Europe.
Fletching on
arrows were fastened with birch bark tar, and
rawhide lashing and birch bark tar were used to fix
axe blades in the Mesolithic period. Birch bark tar was more frequently discovered in archaeological contexts dating from the
Neolithic to the
Iron Age. For example, birch bark tar was identified to serve as an adhesive to repair and decorate/paint ceramic vessels, as a sealing/waterproofing agent. A well-known example of birch bark tar
hafting during the copper age is
Ötzi’s hafted arrow points and copper axe. Multiple discoveries show that birch bark tar was also used to assemble metal artefacts, such as pendants and other ornaments, on both a functional and decorative level. During the
Roman Era, birch bark tar is mostly replaced by wood tar, but birch bark tar is still used, for example, to decorate hinges and other bone objects.
Russia leather is a water-resistant leather,
oiled with birch bark oil after tanning. This leather was a major
export good from seventeenth- and eighteenth-century Russia, as the availability of birch bark oil limited its geographical production. The oil impregnation also deterred insect attack and gave a distinctive and pleasant aroma that was seen as a mark of quality in leather. Birch bark tar is also one of the components of
Vishnevsky liniment. Birch bark tar
oil is an effective
repellent of
gastropods. Birch bark tar oil has strong antiseptic properties, owing to a large amount of phenol derivatives and terpenoid derivatives. Birch bark tar oil was used in the eighteenth century alongside
civet and
castoreum and many other aromatic substances to scent the fine Spanish leather
Peau d'Espagne. At the turn of the twentieth century, birch bark tar had become a specialty fragrance material in
perfumery as a base note to impart a leathery, smoky note in fragrances, especially from the leather and tobacco genre, and to a lesser extent in
Chypres, especially
Cuir de Russie perfumes and fragrance bases, typically together with castoreum and isobutyl quinoline. It is used as an ingredient in some soaps, i.e. the scent of
Imperial Leather soap, though other tars (i.e. from pine, coal) with an equally
phenolic and smoky odour are more commonly used in soaps as a medicating agent. == References ==