Bob rocks! As far as materials go, I think any type of stone would look nice here and I don't have a preference. My only thought is that the view of the model there makes both the brass and the marble look quite dark and dull. I suppose the lighting on the object will vary depending on the placement and the light hitting it in game, but I do miss the brilliance of the concept version. This lovely piece looks like it should be producing its own glow.