Birch bark tar

[citation needed] A piece of 5,000-year-old chewing gum made from birch bark tar, and still bearing tooth imprints, was found in Kierikki, Finland.

[20] 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.

This leather was a major export good from seventeenth- and eighteenth-century Russia, as the availability of birch bark oil limited its geographical production.

[26] The oil impregnation also deterred insect attack and gave a distinctive and pleasant aroma that was seen as a mark of quality in leather.

[28] The repellent effect of birch bark tar oil mixed with petroleum jelly and applied to a fence can last up to several months.

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.

Birch bark pitch made in a single pot: The birch bark is heated under airtight conditions, the final product consists of tar and the ashes of the bark.
Modern way of producing birch bark tar in a single pot: the birch bark is heated under airtight conditions; the final product consists of tar and the ashes of the bark.