This photograph shows the process of grinding dry pigment into a paste for paint.The pigment used here is indian red.The same color used in the dry panel in the photograph above.The glass tool used to grind the paint is called a mueller.The flat bottom of the glass has a slightly rougher texture,like etched glass.Pigment is first poured onto a peice of glass,then the mueller is used to crush it into fine particles.After crushing,a side to side motion is used to make the pigment as powdery and uniform in texture as possible in preparation for making it into paint.If the particles of pigment are too coarse,not ground finely enough the lime plaster doesn't absorb them effectively,and the aesthetic result may not be pleasing.