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Marble floor

We received a call from a homeowner for whom we recently restored all of her marble tile, bathroom showers, floors, vanity tops, cleaned- polished and then sealed to nearly new condition to her complete satisfaction. The work was within 3 months and she stated “there’re spots growing on my marble tile and I cannot figure out what happened.” Well, we did our best to alleviate any fears and booked an appointment to do a site inspection.

Site Inspection of the Client’s Marble Floor Restoration Needs

Upon arrival I took some measurements of the natural stone outside and inside to determine the relative moisture of the marble tile to rule out any water evaporating up through the tile from below the thin set level. There are situations where a plumbing leak can cause water to be absorbed and through the process of chemical reactions with concrete and mortar beds, it is possible to get mineral deposits or etching (more on that in a minute) on the surface of stone from what’s happening below the tile surface. The moisture meter readings confirmed moisture content of below 1% thus we could rule out any water leaks below the surface. Upon further inspection of the spots, literally getting down on ones hands and knees and running a finger on them, revealed conclusively; surface etching. Now how could this have happened? Let’s understand what etching is as it relates to natural stone, in this case marble.

What is Marble Etching?

Marble is a fairly soft stone and it is prone to marking because of its calcium carbonate makeup. Acid reacts with calcium carbonate and literally eats away a tiny bit of the surface, creating dull spots known as etches. Any splash of lemon juice, any drippy jar of tomato sauce, or wine is going to leave a subtle mark. An etch is not a stain. It is an actual changing of the stone itself, like a scratch. It’s not really a discoloration; it’s a dulling. In the bathroom environment you have to start looking at what came in contact with the stone.

Uncovering What Happened to the Marble Tile

In order to uncover what happened you have to ask very specific questions. When did this start to happen? Is it everywhere? Look around the bathroom and see if anything could have spilled. Re-examine the pattern of spotting on the tile. What process do you use to clean the floor? Who cleans the floor? Follow me here? If you ask specific questions you eventually get to the answers you need. The pattern of spotting was very consistent throughout. In this case the same pattern was on every bathroom floor and based upon the pattern everywhere it was pretty evident something was sprayed. Then I heard “my housekeeper knows” and that’s all I needed to hear. Accidents happen and in this case that is exactly what did happen. The housekeeper thought they were using a stone specific cleaner when in fact they accidentally sprayed a non ph neutral chemical on the floor and because it only takes a few seconds to etch, the spots on the floor were due to a chemical etch. It happens, and when reaching for the right cleaner, if it’s similarly marked to any other chemical cleaner, an accident is born. Thankfully in this case eliminating the etching required some machine cleaning employing diamond abrasive technology and a little bit of water which is the methodology behind marble polishing. Within a couple of hours all the marble floors were returned to their fully restored and highly polished condition.

As for preventing an accident again down the road, a little continuing education with the housekeeper was conducted and proper labeling of the right floor cleaner and that’s about all you can do. It doesn’t take much to etch natural stone in this case, marble, but any natural stone can be etched. You just have to be careful and deliberate, always checking you have the right product for the right job before any application.

We’re glad we were able to help and this includes covering the basics with the homeowner’s housekeeper. Both of them are better understanding of what can happen and how to prevent that next accident.

For more about natural stone care and restoration, marble polishing services and much more, please visit our other blogs, see our website, click below or call and ask for Skip!

Skip Jankoski

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