I was still in a experimental mood as I considered the best way to achieve the "dapple effect." I remembered a technique in watercolor painting, where you sprinkle sand or salt on the wet paint and the paint beads around the objects, leaving little light splotches when dry.
Important: I knew watercolor paint was water soluble, which meant if it didn't turn out, I could simply wash it off and no harm done.
I tried the technique out on a blister pack - by painting my white mix, letting it dry, then painting gray watercolor and sprinkling on some ballast (which I figured was the right size for the dapples). The results were encouraging enough that I tried it on the horse.
I think the hardest part was getting the ballast particles in the right place on the horse's belly. I moved them around with a sculpting needle, and this may have helped wreck the effect. At any rate, I'll share the result here, but obviously this was a failed line of inquiry.
(I'm not giving up on the technique entirely. It may have some uses on corroded machinery, for instance. Somewhere where precision and grace aren't called for...)
But back to the project at hand - eek! I quickly wiped off the watercolor, and then took a more traditional route with the dapples.
