Re: resinotype question
Every earth and oxides, lampblack, etc. are very good pigments, though some of them may be too weak (see raw umbra). I prefer to not use organics, because they must be heated up to about 120°C and you don't know if they decompose or not, so you need to be teste each one to see if it fades or changes its colour.Do you happen to know which pigments might not be compatible with this process?
I HIGLY DO NOT recommend trying to heat Prussian Blue (ferric ferrocyanide). The light acidity of the rosin and the heat decompose it developing cyanhydric acid.