Beeswax Marble Medium
This one is really fun! I'm still using only wood panels to paint on, but this medium almost seems flexible enough to take up residence on canvas. Experiment at your own risk, of course.
This, or something similar, might be a candidate for a material used by Caravaggio. I'm looking for something with the translucency of beeswax, the malleability to be marked with the wrong end of a brush, and the firmness to hold shape once dry. Caravaggio worked very fast, so the fact that this stuff will be worked very dry and has the potential to blend color like no other doesn't hurt, either.
I've just begun experimenting with it; the final addition of a very small amount of quark seems to bring the thing to life, so to speak. It just melts together beautifully from that point, and the home-made oil paints blend right in like a dream. But so far I'm keeping the quark out till the last minute and mixing in that final ingredient only when I'm ready to put in the pigment. The ingredients in the main body of the medium are inert and will stay fresh indefintely, but I'm not so sure about the quark.
Beeswax Marble Medium, Body
1 oz. beeswax, melted
1 t. borax
1/4 C precooked walnut oil, heated
app. 2/3 C marble dust
Add borax to hot beewax gradually, stirring well. Don't worry if it starts to fall out of solution. The borax will melt back in once all the other ingredients are added. Add hot oil to beeswax mixture. Blend well. Add marble dust slowly and mix in until a desired consistency is reached.
Add as needed to make an emulsion to mix with paint:
Small amounts (the size of a fingernail) of quark. You can blend the quark and beeswax medium on your palatte as you work in the paints.
The body of the beeswax medium is so inert, it can be stored easily without refrigeration. It seems too stiff to put in a tube, so for now I plan to roll it into little marble-sized balls and keep it in a ziplock bag. I might just dust the marbles with marble dust to keep them from sticking together.