Waterproofing a Basket with Pine Pitch — Sealed Container for Liquids

Before pottery, humans needed waterproof containers for storing and transporting water, cooking by hot-stone boiling, and fermenting beverages. One of the oldest solutions was coating a tightly woven basket with pine pitch (or birch tar) to seal the gaps between the weave. Many Indigenous peoples of western North America used pitch-lined baskets as their primary cooking and water-storage vessels for thousands of years. The technique requires a very tightly woven basket (coiled construction works best) and properly prepared pine pitch that is viscous enough to coat but not so hot that it burns the basket fibres. The pitch fills every gap in the weave and, once cooled, creates a rigid, waterproof shell that can hold water indefinitely.