is a tree which grows in different sizes depending on the environmental conditions mostly in Ilam, Kordestan and Lorestan. The fruit is picked in summer; then its soft inner part is dried, cut and powdered.
Dyeing with this plant can be used without mordants as well because it is full of tannin. However, alum, chromium and tin are respectively used to create the colors of cream, golden and orange.
For the cream color, a small amount of oak powder is put in the bowl and wool fibers are added to the boiling color solution and kept there for half an hour; then the fibers are taken out and boiled in a mixture of potassium dichromate and acetic acid for 15 minutes. Then they are drained and dried. With alkaline substances and iron sulfate, oak creates respectively brown and gray.
- Book Encyclopedia carpets from Iran, Mr. Ahmad Daneshgar