Telling the difference between a stain and an etch mark on marble is quite simple.
An etch mark typically only occurs on marble and limestone, is the result of an acidic substance, (vinegar, lemon juice, coffee or toothpaste), coming in contact with the stone and reacting with the calcium carbonate in the stone. It will leave a dull spots or cup rings on polished stones. A stain, which can happen to any stone, granite included, is the result of either organic or inorganic matter coming in contact with a stones surface and leaving what can be a permanent mark on the stone. A good rule of thumb is that etch marks are lighter in color than the stone, stains are darker in color. A poultice can help remove a stain but will have no effect at all on an etch mark. IF you have etching you need to call in Boston Stone Restoration to diamond hone the surfaces to remove the damage.
If you have determined you have a stain you need to access what caused it. Grease and rust stains seem to be the most common. Due to the porosity of natural stone, stains can occur from both the inside of the stain (rust) or from the top down (grease).
One potential solution to both of these problems is to apply a poultice to try to draw the stain out of the stone. The difficulty is that sometimes multiple applications are necessary to remove the stain all or most of the way. And that can get expensive for a customer who has to pay for a service call every time a professional goes out.
So here is our DIY recipe for a poultice. This recipe is best for rust stains. If the stain is grease, use stripper degrease instead of hydrogen peroxide .Once a stain is successfully removed than you can call Boston Stone Restoration to polish the stone back to the level of shine you desire!
STONE POULTICE RECIPE:
- Hydrogen peroxide-40% by volume.
- Unscented baby powder or talcum powder
- Plastic cup
- Plastic wrap
- Razor blade
- Masking tape
- Plastic putty knife
- Stirrer stick
HOW TO APPLY A POULTICE:
- Pick a test area (approx. 16″x16″) that has the most damage or staining to it.
- Combine the peroxide and the baby powder in the cup and mix until it is a paste about the consistency of peanut butter.
- Apply the paste to the stained area with the putty knife- about 1/4″ thick.
- Cover the area with plastic wrap.
- Tape down the edges using masking tape.
- Use the razor blade to cut one or two slits in the plastic so it can breathe.
- Allow the paste to stay on the counter for 24 hours.
- After 24 hrs., use the plastic putty knife to scrape off the now dried paste.
- Rinse the work area with water and dry with a paper towel.
- After the surface is completely dry, compare the test space to the rest of the counter and evaluate your progress.
- You should see a distinct difference.
- Repeat the process in sections of the counter until desired result is achieved.
Note** There are several different recipes for different types of poultices that remove different types of stains. You can always adjust the recipe. For example, a stripper/degreaser can replace the peroxide when a grease stain is present. A product called Iron Out can be substituted when dealing with rust stains.
Note** Do not be afraid that you will harm your stone by working on it. The rule of thumb with poulticing is “if a stain can go in, a stain can come out.”
Note ** Remember to wear your gloves!
Good luck- and happy poulticing!