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... Read More

Lichens and mosses produce oxalic acid, which can destroy calcium-based stones. Since they are considered plants, they will also attract moisture, which can cause all kinds of problems with the stone, including spalling. They can also cause the stone... Read More

When you should clean an old stone building will depend on which climate your building is located in. If located in the northern hemisphere never schedule cleaning during the winter months, since freezing temperatures can cause the stone to spall.... Read More

Curling in green marble can be a serious problem when the marble is set in a wet mud or thin-set. The Marble Institute of America recommends that green marble be set with an epoxy-based compound. Check with the installer and see what has been used to... Read More

It depends on what kind of green marble you have. I would guess that the green marble in your bathroom is an Asian green. If this is the case, you will never get a deep shine on this marble. These stones characteristically have a clouded shine. If,... Read More

First, you need to determine whether or not the white specks you describe are on the surface of the marble. If you can’t clean them off, chances are they lie below the surface of the marble. If this is the case, it is possible that there are... Read More

Black marble, especially Negro marquina, is very susceptible to spalling. Spalling is a condition in which the stone flakes off and falls apart. Several factors can cause spalling: excess moisture, choice of setting material and method, the polishing... Read More

I am assuming that the black marble you are referring to is negro marquina. If this is the case you will find that this type of black marble is very susceptible to spalling of the veins. Over-polishing with either powder polishes or recrystallization... Read More

It sounds like moisture is trying to escape from the marble. This is a problem if a non breathable coating is placed on the marble. You will need to strip the coating off the floor and allow it to dry for several days. I would suggest polishing the... Read More

The problem may be with the strippers that have been used. Many strippers have an alkaline pH and this can lead to the deposit of alkaline salts in the pores of the granite. If the stripper is not rinsed throughly and any stripper residue is left... Read More