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

Staining from silicon can be very difficult to remove, but not impossible. First remove all the silicone caulking; removal of the stain will require the application of a poultice and a strong solvent such as methylene chloride. Several applications... Read More

If you apply a silicone impregnator to the back of a tile before setting, this may cause a bonding problem. Since most setting mortars are water based they will want to repel the water. Use an epoxy-type setting material. TIP: Before setting any... Read More

The yellowing and graying of certain Italian and Greek white marbles is a common problem that I see all over the country. There are several possible causes for this condition: Maintenance technique-Take a close look at your maintenance program. Are... Read More

I would call the contractor, but it may not be necessary to replace the panels. These dark circles may be the result of moisture bleeding from the setting mortar. It is common for panels to be installed by spotting the backs of the panels with... 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

This a common condition, especially if the floor is new. When the marble is installed, it is set in a mortar base that is wet; as the moisture leaves the mortar, it carries with it dissolved salts which are deposited on the surface of the stone. This... Read More

Q. Natural stone tile installation has water marks that aren’t fading after 2 weeks of installation. Should I apply a poultice to remove the moisture? MSI sells the stone. It's called white oak. It's honed marble, 24 inch tiles, and... Read More

Q. I have an (intentionally) distressed marble seat in my shower. After years of use, there is a build up of white on top of it. How do I get ride of it? Thanks.   A. White residue on the top of stone can be attributed to several things. Ask... Read More

  Q. What can we do to clean marble lobby floors in our various commercial buildings? A. The yellowing and graying of certain Italian and Greek white marbles is a common problem that I see all over the world. There are several possible causes for... Read More