The openings or sinkings of cardboard mounts are cut from close-grained board made for the purpose. The surface of the cut-out mount is coated with gilders' thin matt size, which is made by mixing fairly strong size with the raw material. Generally two or three coatings will be necessary, each coat being allowed to dry thoroughly. The surface is next papered down with old emery-paper, washed, polished, and finally covered with English gold leaf. Much experience is required in this particular branch of gilding. The primary cause of failure is in getting the matt size and subsequent weak sizes too strong.