Q. I have to two 200 year old antique marble dresser tops. One is fairly clean but the other has some brown spotting on it and I am not sure how to clean it or what is causing it. Neither of the tops are polished. I have seen on "Antique Marble Mantel Cleaning" that MB Stone Care MB2 is the recommended cleanser. I would appreciate any insight into this problem.

 

A. To remove a stain --any stain -- it is important to determine what caused the stain. Without knowing or having an idea what the brown spotting is, it is difficult to determine what process to use.

 

Brown spotting could be oxidation within the stone mineralogy. Certain marbles or compact limestones contain minerals such as iron sulfide (pyrite) or iron carbonate (sideride) minerals, which may result over a period of time extensive brown staining. This staining is like a tumor within the stone and is irreversible.

 

On the other hand the brown spotting can be an organic stain (coffee, tea, colouring agents of dark sodas.) This type of staining can be removed by using a poultice process. (Refer to the stone care guide for instructions on creating a poultice.)

 

For general cleaning of the stone I recommend to use MB-5 or MB-9.  MB-2 is a heavy duty product formulated for cleaning heavy soiled stone surfaces. (Click here for MB Stone Care products)

Regards,

Reg Pinto
The Stone Doctor