verdaccio

Verdaccio is an Italian name for the mixture of black, white, and yellow pigments resulting in a grayish or yellowish (depending on the proportion) soft greenish brown. It is neither warm or cold, color tones applied over absorb the value without changing corresponding properties.

Verdaccio became an integral part of fresco painting, in which this color is used for defining tonal values, forming a complete monochromatic underpainting. Often architectural details in frescoes are left in verdaccio without any additional color layers; a notable example is the ceiling of the Sistine Chapel, where verdaccio underpainting can be clearly seen, left as it is on all architectural details of the composition.