Quote - Okay, here's my first attempt that even gets close (with really poor rocks, but again its just a first attempt).  As you can see, its doing the exact opposite of what I want.  How do I get the replicator to switch from white to black in the shader?

You can edit the shader and in the shader options, if your black and white distribution is a texture map, you can just check the "Invert Color" option in the texture properties. If your black/white distribution is procedural, then it might be trickier, because it will depend on the type of procedural shader you are using.