Problems and Solutions
Why does white marble turn yellow?
The problem of yellowed white marble is not uncommon. Although flooding is a common cause there are several other reasons this color change will ocurr:
- Improper maintenance
As marble wears, the highly polished surface begins to disappear. The wearing of this polish causes the surface to become rough and is a magnet for dirt. If improper cleaners are used, this dirt begins to accumulate in the pores of the stone and will turn yellow.
CURE: If you suspect yellowing due to improper maintenance the marble tile will have to be cleand with an alkaline marble cleaner. Apply the cleaner to the marble and scrub with a soft brush. Be sure to rinse the floor thoroughly. If aftr several sessions of cleaning the yellowing is not removed then proceed to the next cause.
- Wax build-up or coatings
Many marble floors are coated with waxes, acrylics, urethane and other coatings. Many of these coatings are not specifically designed for use on marble floors. Some of these coatings are of poor quality and will begin to yellow.
CURE: To remove yellowing due to a was or coating buildup, the marble will need to be stripped with a commercial was stripper.
- Iron staining
Many white marble tiles contain naturally occurring deposits of iron. Iron is a mineral found in stone and can occur randomly throughout the stone. If iron is present in the marble tile, it will begin to oxidise when exposed to water or other oxidisers such as acids and household bleach.
CURE: The process is difficult to reverse and replacement of the tile may be necessary, even if there exists a removal technique that has proved successful in several cases. Before testing such a procedure it is important to first determining if iron is the cause.