More specifically, compressed charcoal sticks used for drawing. I don't know if it's the paper or the charcoal itself, but it just won't blend very well. I had to draw a full value drawing (with complete shading) and I still ended up with the original lines I drew before blending. Granted, the white space in the area turned gray, but the damned base lines are still there. It looks like crap. I have crosshatching lines where it should be a uniform gray. That's why I prefer digital art to traditional. Digital is so much easier. [/rant]