Part of the wall paintings are frescoes which were made by first plastering the cave wall with a mixture of clay and straw or hemp as a binder to create a flat surface, the way walls are plastered today.

• 有一类壁画的制作程序，是先用泥涂平窟面，涂壁的泥土里，先加入铡碎的麦草或麻布做筋，这和现在涂土墙的办法差不多。