Latex paint smudged onto fake river stone fireplace and mortar
Use some painters tape and plastic to mask off the wall below.
Carefully remove the pieces of dried latex with a razor blade (If Possible).
Dip a toothbrush into rubbing alcohol and gently brush over the smudge.
Wet another toothbrush and pour dish detergent directly on the bristles.
Gently scrub the grout.
Dip the toothbrush into clean water and rinse.
Dab with a clean damp cloth.


Repeat as necessary. The paint will eventually all come out and you wont harm the grout.


Send that painter a bill.