This is because the acid removes the surface material and exposes marble that was ordinary below the surface.
Acid marble etching.
Soda spill on limestone.
If you have a honed white marble surface that shows acid etching you can either call in a stone professional to treat the surface or you can try the following technique on your own.
Sprinkle a scrubbing cleanser onto the surface with a few drops of water.
Etching is a corrosive chemical reaction that essentially eats at the marble.
Lower than a 7 is on the acid side and higher than a 7 is on the basic side.
Acid stains such as by a toilet bowl cleaner or battery acid cause what is known as etching on marble.
Thats why it looks so dull compared to its beautiful surroundings.
Etch marks on polished marble look much worse than on honed marble.
Acid etching is the process of applying hydrochloric muriatic or buffered phosphoric acid to a slab then rinsing it off with water.
Here is a list of some surprising substances that can etch stone.
Take a scouring pad and move in a circular motion to hone the material.
When my husband and i were researching our kitchen renovation a couple years ago marble countertops were the clear frontrunner but we were nervous about the inevitable etching.
Marble etching occurs upon contact with acidic foods and drinks like coffee soda wine alcohol and when harsh products like bleach vinegar ammonia and most common brand name cleaners are used for cleaning marble.
So we paid visits to every marble topped bar and marble furnished ice cream parlor we could find cocking our heads to the side peering down long polished surfaces to examine the damage left by countless drippy.
Please note that scratch marks from sample preparation will also become apparent.
The etchant will darken austenitic grains attack sigma phases and show grain flow.
If needed a professional marble restorer can always be called to repair the damage.
What the acid has done is remove part of the surface of the marble and what is left behind is marble that was below the surface and is therefore unpolished unlike the rest of your marble.
For more information see our 7 facts about etching on marble.
Marble s reagent aka marble s etch is a metallographic etchant for etching 300 series austenitic stainless steels nickel and cobalt based superalloys.
An etch is not a stain and cannot be prevented by using even the best penetrating stone sealer.
Substances that contain acid ammonia and alcohol can etch marble meaning that the finish or the shine is removed if you accidentally spill one of these three substances.
Think of it like a burn that removes the finished.
This newly exposed marble is not polished and looks very dull compared to its polished surroundings.
These stains can be difficult to remove but not impossible.
This product is made with reagent grade chemicals.