Pastels have been added on now. Several light layers and a few thicker ones. There is a limited amount of layer that can be done. The chalk begins to “gum up” or mix into a neutral or “mud” color after too many layers and it will not be "workable" anymore. More layers can be added but it will not produce anything but more "mud." Therefore, the picture needs to be coated with a few layers of “fixative.” Fixative is similar to varnishes in that it holds down the media and coats in a protective/fade-proof layer. Pastels tend to not adhere well and the fixative holds it down. Fixative is different from varnish or other coatings in that additional layers of pastels or other media can be added on over the top. With varnishes, there is a slick surface that will not allow anything to adhere to it. That is varnish's purpose, to protect and to allow it to be cleaned without removing any of the art work media. Next step will be a few layers of fixative.