At first, the head and tailof the bone are cut and soft tissues are removed. Then, it is boiled in a mixture of water and hydrogen peroxide to remove the oils and other by productsand after that it’s cut into different pieces. Fornicated part of the bone is used for the lid of the boxes and flat part is used for the sides of the boxes and also for small paintings. The edges of these different pieces are polished to become smooth and then are folded to make a box. Finally, it’s immersed inside gasoline for a couple of days in order to be degreased properly.