[George]

I was not able to locate a primary technical description from Syd Solomon himself detailing the exact chemistry of this process, but the description you shared is consistent with a casein-based resist method used by some painters in mixed-media work. In that approach, a water-sensitive protein film (such as lactic casein) is applied to selected areas as a temporary resist over an absorbent ground. Additional paint layers are then applied, and after drying, the casein layer is softened and removed with water, revealing the protected area beneath.

Regarding Ceracolors Fluid Medium, it would not function in quite the same way.

Ceracolors Fluid Medium is a beeswax emulsion rather than a casein solution. Because of the wax content, it is designed as a permanent painting medium, not a sacrificial masking layer. Once dry, it tends to remain integrated into the paint film rather than dissolving cleanly and predictably, as with a removable casein resist. Attempting to use it as a masking fluid would likely be messy and unreliable—it may leave wax residues, interfere with adhesion of later oil layers, and would not “wash off” in the same controlled manner.

So, for a truly removable resist technique, Ceracolors Fluid Medium would not be the best choice.

If you want to experiment with a Syd Solomon–style resist approach, a better option would be:

• a weak casein solution
• diluted hide glue or gelatin (used carefully)
• another intentionally water-reversible temporary resist

This should only be tested on properly prepared absorbent ground—not on an oil or nonabsorbent surface—since removability depends heavily on the ground structure.

I would strongly recommend testing on small panels first, because excessive moisture during removal can disturb underlying paint layers or grounds.

In short: Ceracolors Fluid Medium is excellent as a painting medium, but not as a removable masking fluid for this type of resist technique.