I have been trying to find information about the pigments that were used in tattooing before the advent of modern inks. I have found plenty on Polynesian tattooing, but my setting is more analogous to southern France. I remember hearing that the “Ice man” found in the Alps had tattoos done with charcoal, and I’ve read about a Scythian chieftain with elaborate tattoos made from soot. And of course we often read about the Picts tattooing themselves with woad, although I think there may be some scholarly controversy over this. My character has access to some charcoal and ash, along with red ochre and perhaps some other dyestuffs. How much of this material could she potentially use for tattooing? If there are suitable pigments that could be made from tree bark, too, that would be helpful to the story. (Hmm... oak galls were used for making ink in the Middle Ages--could such an ink also be used for tattooing? Can any ink be used as a tattoo pigment?)
Any resources or insights that any of you might have will be much appreciated!