need to find out type of grout.. with the new urethanes and wb epoxies, may not be cementitious, especially being commercial may have been spected different.
then best to do sample, its a wall, so if its not easy removel, can be PIA
Thanks, that would be a hell of a curveball.
Based on my 15 minute crash course on different grout types that I just concluded, I think it is a cement grout.
My only test was to give a few of the heavier deposits a good stiff finger rub, and it "powdered" down as I thought it would.
From what I read, I am assuming an epoxy product would have not reacted the same, and would have felt completely different, and not have broken down so easily.
It's located in an indoor mall, so probably less reason to use an epoxy.
My main concern is that since it is black and textured (probably the worst 2 characteristics to have in such a situation) , I am worried that if I do not get it off completely, it will show when dried.