Etching and Watermarks on Marble Surfaces

More marble is damaged by acidic chemical exposure than any other single source. Most of this damage is from accidental spills. However, a good percentage is caused by the use of improper cleaning chemicals like in your shower case.

I speak to literally hundreds of clients each year with chemically damaged marble. Here’s the breakdown (in order of frequency) of the events that damaged their stone:

1. Accidental Spill of an Acidic Substance (orange juice, lemonade, wine, vinegar, etc.)
2. Use of Improper Cleaning Chemicals (including accidental exposure)
3. Contact with Cosmetic Products (facial cleaners for acne, citrus based soaps & shampoos, etc.)
4. Embedded Watermarks and Stains from Cups, Glasses, and Bottles
5. Personal Accidents Around Toilet Bases (oops, I missed…)
6. Physical Scratches and Stunning
7. Pet Accidents (urine & vomit)
8. Embedded Oils Stains (food substances, cooking oil, butter, essential oils, etc.)

As you can see, the top 5 causes of damage are either etches or watermarks. Let's explore each in more detail:

Etching

Acidic spills (orange juice, lemon juice, grapefruit juice, wine, vinegar, Margarita mix, certain cosmetics, “tile cleaners”, “bathroom cleaners”, “tub & toilet cleaners”, etc.) are the single-largest cause of etching. They will etch marble surfaces immediately – whether they are impregnated (sealed) properly, or not. Etches appear on your marble as spots or areas that are much duller than the surrounding stone, and they do not improve with normal cleaning techniques.

Etches can be classified into three categories:

Minor: Results in loss of shine / reflectivity. No roughness can be felt on the etched area when a thumbnail is scraped across the surface from an undamaged area into the affected area.

Moderate: Results in loss of shine / reflectivity. Slight roughness can be felt on the etched area when a thumbnail is scraped across the surface from an undamaged area into the affected area, but there is no visible pitting or “cratering”. If the etch has caused a crater, you will feel (and sometimes see) a drop-off when performing the thumbnail test.

Severe: Results in loss of shine / reflectivity. Significant roughness can be felt on the etched area when a thumbnail is scraped across the surface from an undamaged area into the affected area, and there is visible pitting and/or “cratering”. Severe etches over 1/16 of an inch deep will require an epoxy patch or replacement of the stone.

You must make every effort to ensure that acidic substances (like those listed above, and others like them) do not come into contact with your marble. If they do, remove them immediately from the surface by wiping them inward on themselves to avoid spreading to uncontaminated areas.

In order to remove this type of damage you will need a professional like Marble Doctor that will use a diamond polishing system. Any other systems will only cover the problem ( waxes, crystallization). Once the diamond restoration process is complete we usually set our clients with a maintenance program.

(picture example of a dull etched marble before and after)