of course you can etch it if ya stoopid about it.Just saw this. Acid on Marble? You're going to etch the crap out of it. Why do people put marble in their showers!
My reasoning is to do initial weak acid wash with towel to get initial layer off cause it appears pretty bad. The acid will weaken even more once applied. I wouldn't allow dwell time any more 5 sec or so and rinse. Sections at a time. After thats done, use dip pads.looks to be "etched" or honed as can possibly be, so whats to lose....
and what happened to our Reno buddy?
once you have THIS shower owner committed to paying you, what would be your first "cleaning " step?
Looks to be already heavily damaged from "acid cleaning", hence the damage directly below on floor.