An Italian name for a paint mix with black, white and yellow pigments which create a warm grey to olive greenish colour. In fresco-, tempura-, and oil painting verdaccio is used to define the tonal values in and acts as a complete monochromatic underpainting.
Flemish painters used verdaccio as the so-called dead layer. I.e. the 5th of 7 defined layers to take out the warmth of the primer further down. 1 part raw umber and 1 part ochre was the starting point here.
The tonal range between white – olive green and black made the dead-layer look as if the whole painting was complete except that it was lit by moonlight only. Verdaccio was in effect used as the skeleton of the painting before colours and highlights were applied to finish off the painting.