Here I am once again faced with a rock to draw on. I learned a lesson with this one; I covered the rock with silver Sharpie for an undercoat which made it really slick, resulting in a total loss of pen control when drawing the pattern. Reminds me of something Paul Simon said about "Slip Sliding Away". It was fun though. I have learned not to be too concerned with the outcome, rather just keep drawing and coloring and shading and having fun and the end result will often times surprise you in a pleasing way. There's a gray pen in the Sharpie set I have that I used for shading around the spirals. It actually worked without totally obscuring the lines underneath. Hafta give it some more mileage. Sorry about the wordiness - Enjoy the rock.