The use of a pressure washer on marble should be avoided. Pressure washing forces water into the pores of the stone and can cause the development of efflorescence. If you must use a pressure washer make sure that the operator is skilled. Do not use a... 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

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. My unfilled, but sealed (with a lithofin product) travertine needs a good clean before resealing. What is the best technique for this? There is dirt in the holes, which is obviously worse in heavy wear areas. Thanks A. The best way to clean... 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

This is a problem in northern climates where de-icing salts are used. During the winter months deicing salts are used to melt the snow and ice. When the weather warms, the salts are dissolved and carried into the granite. When the granite dries, the... Read More

Q. Hi! We have outdoor noce travertine - unsealed - on our pool patio deck. We had a "dog party" last week and one dog loved to swim. He repeatedly jumped in our pool and then ran through our plant beds, tracking mud all over our travertine. The mud... Read More

Q. In response to your follow-up question about our travertine patio stained with mud, our patio travertine is directly on dirt. I will try a tile and natural stone cleaner as you suggested and hope for the best! Our travertine does have the wet look... Read More

  Efflorescence - Removal and Prevention   By Frederick M. Hueston www.stoneforensics.com The crystallization of soluble salts in Historic masonry causes severe deterioration of the substrate. This crystallization is called subflorescence. These... Read More

  Efflorescence - Removal and Prevention   By Frederick M. Hueston www.stoneforensics.com The crystallization of soluble salts in Historic masonry causes severe deterioration of the substrate. This crystallization is called subflorescence. These... Read More