Sumac is a small tree. Its fruits are used as a spice in the Middle-East. The bark and the leaves have a strong tannin content and have been used by tanners since the Antiquity (Greece, Egypt) : the botanical name Rhus Coriaria comes from the Latin “Coriarii”, meaning tanner. Sumac is often preferred because of its excellent light-fastness (compared to the other vegetables) as well as perspiration fastness.
The leaves contain up to 30 % of a tannin, which is the condensation of Gallic Acid, Digallic with Glucose.