How to remove mortar from cultured stone?

Question

I smeared some on it by accident while grouting the joints.

Thanks

Answer 1

Use "brick-clean" or similar muriatic/hydrochloric acid as sold by builder's merchants, follow instructions, it works very well, I use it all the time

It's not expensive $8 a gallon container, terrific for cleaning moss from boulders/ patios etc.