Sgraffito

In the past, it was an artisanal, masonry technique. The plaster was colored with burnt straw and coated with bright mortar. Tin stencils were applied to the light mortar and patterns of an eminently graphic nature were cut out.

Sgraffito black and white

Lime mortar - like for intonaco, only slightly fatter - is colored in boxes with black alkali-resistant paint. We mix it well and leave it for 3 - 4 days. After this time, we mix again and impose on the aricciato.
We level this layer with a bottle (after emptying it first) and wait 30 - 60 minutes.
Then we dilute the lime cake with water (to the density of lime milk) and cover the black intonaco with this solution using a brush. We cover twice, every half hour.
As soon as the surface becomes dull by soaking the water deep into the plaster, we sprinkle the drawing.
Now, with a penknife-like tool, we cut through the thin layer of whitewash and expose the black plaster.
As in fresco, here we must use the so-called "days".

Multicolor sgraffito

Wanting to get a sgraffito, such as a tricolor - black, red and yellow, we put on as intonaco two layers:
first black (3 - 4 mm),
then red (2 - 3 mm).
The third layer is applied with a brush, tinting the milk of lime yellow.
We always put colored layers of plaster from the darkest one.
Wanting to get red, we cut the yellow layer, and black - yellow and red at the same time.
We can also divide the whole plane into colored fields by applying the last layer in different colors.
You can also combine two techniques - sgraffito and fresco, except that with fresco we cover the last layer (under the fresco we give a white layer for color purity).
In sgraffito, half a kilogram of dye is taken for 1 square meter of painting surface.
There is also another type of sgraffito, something like intonaco in plaster:
In intonaco, ornaments are cut all the way through the thickness, up to the aricciata.
Then a colored mortar is imposed over the entire intonaco.
Later, this mortar is scraped off around the ornaments, which now look like "inset."