^ Very true.
Makes me think of all those great portraits in the Archibald Prize. If you look at them, the textures and colours of the skin even on caucasian subjects will have a lot of life and variation. Sometimes, even shades of green or red are used to illustrate character.
If you're using pencil, you could get a great caucasian skin tone by overlaying colours like pink, brown, gold, silver, yellow or orange. It might change with the direction or quality of the light in the picture, etc.
Like BirdInFlight noted, skin tone is dynamic, and in quality art it won't all be one uniform colour. It might even be darker around the eyes or near the ears, paler on the forehead and cheeks, tipped with pink at the ears and nose on caucasian subjects, etc.
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Alexithymia - 147 points.
Low-Verbal.