The above picture looks like a charcoal drawing...my monitor does not show it with any green.
I use a grisaille underpainting method and usually mix raw umber and titanium white to achieve this.
Sometimes I add yellow ochre to this mixture and it takes on a greenish hue...could I have been using Verdaccio all along and just not have known the name?
See
http://forum.portraitartist.com/show...=&threadid=190