Thanks, Robert. I appreciate the comments.
I haven't tested the solubilities of pan pastels. Mine are basically soft pastels with talc held together with a small dose of methyl cellulose. I'm sure that's what makes them water-soluble. I dabbled a bit with some of the left-overs on a piece of wet wc paper just to see how they work hand here's the result.
They work just like watercolors, but when they're dry you can blend them with your fingers like soft pastels. Neat.
You've got me thinking about other ways to use pan pastels. Hum??