How to Remove Pickling Vinegar Stain on Flagstone

Q. My pickling vinegar bottle (7 percent acidic) leaked on my flagstone (limestone?) floor. I made a paste of baking soda and applied after washing the floor with Marbalex stone floor cleaner. I let the paste sit for the afternoon to no avail. I would appreciate any help to restore my floor. Thank you.

A. Thank you for contacting us. After viewing your images our expert believes your stone is not limestone, but slate, and the discoloration you see is damage to whatever coating is on the slate. If your stone is, indeed, limestone, then what you are dealing with is an etch, not a stain. An etch is chemical damage to the surface of the stone, and stain removal methods will have no effect on them. Some minor etches can be removed using DIY methods, but due to the extent of the damage on your stone, DIY methods are not recommended. Removal of the discoloration and restoration of the finish should be entrusted to a professional stone restoration contractor. To find a Certified SurpHaces PRO Partner near you, contact us.