Painting 3d printed stone walls

In case we ever get to cast 5th level spells in D&D, I had these stone wall fragments to be created for... you guessed it, Wall of Stone.

Spray black.

I tried to finesse about, first by drybrushing Heavy Charcoal, then by layering it on the other surfaces, but it was practically invisible. A few light strokes of lighter grey drybrush were also barely noticeable, so I got out my oldest and most worn drybrushing brush, and went to town.

Cold Grey.

Then Stonewall Grey. 

I wonder if the middle step was needed at all... oh well. 

Also notice the triangular shapes due to how the 3d printing file was defined. No problem, it just adds to the texture.