Limited palette in portrait painting

"(The) position of the warm and cool colours in flesh painting, is one of the most important considerations in colouring; as it is on the opposition of the warm and cool colours, that the vitality of colouring largely depends. Painting with red for your warm and black for your cold, and a mixture of both for your neutral tones, a surprising amount of colour vitality can be obtained, by the right placing of the warm and cold colours." -- Harold Speed

We're working with white, black, yellow ochre and cadmium red in Don Sondag's portrait class at Crealde.  It has been amazing to see the beautiful flesh tones he gets from this limited palette in such a short period of time, usually about an hour or so.  I'm lucky to be able to study with such a master.

Last night we used a few more colors--cadmium yellow light and alizarin crimson and ultramarine blue (no black).  Before I wipe it off, here's the painting I did last night.