After seeing what happened with the MultiCam, I'm feeling ornery.
The natural habitat of the Granite block is free and unfettered rein with Mother Earth and all the fuzzy creatures that inhabit her.
I found the Granite block covered in man made waste and pollution.
I freed her from her bondage and let her breath once again the pure air of oxygen, nitrogen and carbon monoxide.
Please treat her well so that she may bring joy to all makerspace kind.
So to be more direct...The granite block is designed to be flat and true. If you put crap on it, like a can of rusty nails, it WILL get damaged. It will no longer be true to itself or the fuzzy creatures of Mother Earth.