Chapter XII (Xxvi.)
Of the Sgraffiti for house decoration which withstand water; that which is used in their production; and how Grotesques are worked on the wall.
§ 91 Sgraffito-work
Painters have another sort of picture which is drawing and painting both together. This is called sgraffito; it serves only for ornament on the façades of houses and palaces, and is very quickly executed, while it perfectly resists the action of water, because all the outlines, instead of being drawn with charcoal or other similar material, are etched by the hand of the painter with an iron tool. The work is done in this manner. They take lime mixed with sand in the usual fashion and tinge it by means of burnt straw to a tint of a medium colour inclining to pearl grey, a little more towards the dark than the middle tint, and with this they plaster the façade. That done and the façade smoothed, they give it a coat of white all over with the white lime of travertine, and then dust over the (perforated) cartoons, or else draw directly that which they wish to execute. Afterwards pressing upon it with an iron stylus they trace the contours and draw lines on the cement, which, because there is a black substance underneath, shows all the scratches of the tool as marks of drawing.230
It is customary too to scrape away the white in the backgrounds, and then to prepare a water colour tint, darkish and very watery, and with that reinforce the darks, as one would do on paper; this seen at a distance is most effective. But if there be grotesques or leafage in the design, cast shadows are painted on the background by means of that water colour. This is the work that the painters have called sgraffito, on account of its being scratched by the iron instrument.