Every earth red on your palette leans warm. Except one - and that one is the reason a cheek can actually turn away from the light.

Skin shadows are not gray. They are red - and this ancient pigment is how painters have known that for 25,000 years.

Four blues walk into a flesh mix. Only one comes out clean - and the reason explains half of portrait painting.

Terre verte, the verdaccio tradition, and the three mixes that keep flesh from going sunburnt.

Let's start with the fact that there's actually no such thing as skin color. There is a skin tone.