There's a pastel technique I've wanted to try since I first started using soft pastel and that's to use the pastels wet. On first thought, you wouldn't even venture a wild guess that pastels could be water soluble, after all, they're called "dusties" for a reason, right? But I've seen some beautiful backgrounds and special effects from spritzing the pastel painting with water or pushing the pastel around with a wet brush or even using a pastel on a wet surface.
Most of the time, I don't put much of a background on my pet portraits because many of them are on a colored support and don't really require one. But, I've started a new floral painting on Ampersand PastelBord and it really needs a nice background. The painting is a little larger than I normally work and it was getting tedious trying to put in the background with just dry pastel sticks. So I scribbled in the various colors I wanted and used a wet bristle brush to move the pigment around. It works beautifully!
Why am I so surprised? I shouldn't be as pastels are nearly all pigment and that pigment is very finely ground to boot. It stands to reason that if that same pigment used in watercolors will dissolve in water, then it should dissolve in water even in another form. And it does!
I wish I could show you what I've done so far as I'm very pleased with it. I hope to have the memory card reader fixed soon and am planning to go look at scanners today so maybe I can do a little demo for you later.
If you use pastel as a painting medium, I recommend that you try it wet at least in one painting. I think you'll be pleasantly surprised!