Suppose you have an interior granite wall that had some silicon caulking used in the grout joints. The silicon then caused staining along the grout edges. A poultice successfully removed the staining, but then later, the stains reappeared. What... Read More

Q. We have mold buildup in grout joints and surface has film on it. What is best to clean mold and remove film from surface?   A. There are several cleaners that will remove the mold but you must be careful to choose one that will not damage the... Read More

Graffiti Removal Procedure for Stone, Masonry, and Tile Surfaces By Frederick M. Hueston, www.stoneforensics.com If your beautiful building, wall, or other surface has just become the unintended canvas for graffiti, your first reaction might be to... Read More

No, it is absolutely false. There are soft, dark marbles and there are hard dark marbles. For example, negro maquina is a very soft marble. On the other hand Vermont Green is a very hard dark marble. Do not rely on color alone to determine the... Read More

Q.  I have a brand-new bathroom stone vanity and my daughter put her Argan Moroccan hair oil on it (there is a ring where the oil is). What is the best way to remove it? Should I use a de-greaser with a poultice, just a degreaser, or should I use... Read More

Stone Myths By Frederick M. Hueston www.stoneforensics.com Over the past 20years I have heard many stories about the reasons stone will fail, turn color, fade or what ever. Many of these stories are funny and almost all of them are just plain... Read More

Q. Is granite safe? A. You may have caught wind of a report circulating that granite countertops are unsafe, harbor bacteria, and can produce disease. This is absolutely false. NIOSH and the CDC have no reports of granite or any other stone used as a... Read More

The white deposits are salts, which are bleeding through from the grout joints or from the mortar. An acid wash will be required to remove the salts. If the deposits are heavy, try scraping them off before washing the slate with acid. Several acid... Read More

Several excellent grout cleaners are available from your stone care supplier that will not dull polished marble. Try a mild solution of bleach ; use a soft tooth brush to apply the solution to the grout joints and scrub lightly. TIP If the grout is... Read More

This is a condition known as efflorescence. There are soluble salts in the grout coming to the surface. The large amount of water you used dissolved the salts and they are depositing on the surface. Efflorescence will eventually disappear when the... Read More