Cleaning granite steps

Hey guys,
I just wanted to see what you all recommend for cleaning heavily soiled granite steps. These don't have the polished "countertop" looking granite, but rather the more natural looking variety that steps, cobblestone and curbing is make of.
All the cleaning advice I've found on the web is regarding granite countertops and tiled floors.
I was thinking either CLR? Or maybe oxyclean? Forgive my ignorance, any guidance is appreciated.

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