How can I get grout color stains out of my tumbled marble tiles?

Q. We tiled our backsplash with tumbled marble subway tiles. We DIDN'T seal the tiles first (DUMB MOVE). Then we grouted half the kitchen and found that not only did we hate the grout color but it colored our light tumbled marble stones a yellowish tint. Any ideas on how to remove the color and grout on the surface of the stones? Thanks.

A. There are several ways you can remove this film. However it may require the services of a professional. First, try mixing some odorless ammonia and water with a 50/50 mix ratio. Wet the tile and apply the solution with a soft scrub brush. Agitate it and then rinse with clean water. If this does not work you will have to use a mild acid. I would not try this yourself. Contact us for recommendations for a quality stone restoration contractor.

Of course with any chemical or application process first test in a small area.

Fred Hueston
Chief Technical Director, SurpHaces
President, Stone Forensics