Frit is a ceramic composition formed by fusing inorganic materials into a glass by heating them in smelters and quenching them in water. this process, known as “fritting” was developed to render any soluble and/or toxic components insoluble and/or nontoxic. This exercise shows how to apply a png file to a curtain wall system to show in a realistic display how the frit pattern in the glass apears. it currently will show transparent but as of now will not cast a shadow.. thanks, rick kremer asti Ceramic enamel frits contain finely ground glass mixed with inorganic pigments to produce a desired color. the coated glass is then heated to about 1,150°f, fusing the frit to the glass surface, which produces a ceramic coating almost as hard and tough as the glass itself. As an alternative, permanent patterns can be applied to glass with ceramic frit—the frit can be silk-screened on the glass, so that virtually any design can be incorporated. although frit glass is usually installed to afford privacy or increase energy efficiency (by decreasing solar heat gain), frit can also make glass more visible to birds.