Lenape bags are made from full grain “vegetable-tanned” leather, also know as oak leather. Un-sanded to show the natural grain, it is the highest quality leather for a craftsperson.
Vegetable-tanned leather is produced by immersing the hide in a tannin solution of water, ground plant bark, and leaves. Usually the solution contains oak, but it may also use hemlock, birch, chestnut, or other trees. Traditional tanneries contain this solution in earthen pits, while industrial tanneries use modern machinery. Because of these natural materials, it is considered the most environmentally friendly method of tanning.
One of the most notable qualities of vegetable-tanned leather is that it wears well with age, developing a lustrous patina with use. The more it is handled, the better it looks.
Vegetable-tanned leather has a special relationship with water, becoming pliable when wet and stiffening into a hard shape when dry. It is also photosensitive in its natural state. Just a couple hours in direct sunshine can turn the leather from a light tan to a dark brown. Oils transferred from the skin when handling and conditioning treatments will also darken the leather slightly, creating a rich patina over time.