I am doing my second stone project. First was a small river stone wall behind my wood stove and I just used grout between the stones. It was actually more like a tile job, so I had more experience. This job is a stone retaining wall made from old road blocks from the city of cleveland. All granite or sandstone. I am not very "clean" about it, and have mortar all over my stones when I am done. I have read that muratic acid is the way to go to clean it when I am done. Is this correct or is there a better way? I really just don't know how I could keep it any cleaner and actually do a good job.