Stone Care Guide:
Marble, granite, limestone and other decorative stones are durable materials that will last a lifetime. However, if not installed correctly or properly cared for, problems may result that will shorten its life. The following are common problems that may occur:
1. LOSS OF SHINE
The loss of high polish on certain marble and granite can be attributed to wear. This is especially true of marble since it is much softer then granite. When shoes track in dirt and sand, the bottoms of shoes can act like sandpaper on a stone floor surface and over time will wear polish off. A stone restoration professional can restore polish using a number of different techniques.
2. ETCHING
The dull whitish spot created when liquids containing acids are spilled on marble is called etching. Marble and limestone etch very easily. Granite is very acid-resistant and will rarely etch. To prevent etching avoid using cleaners and chemicals that contain acids. Light etching can be removed with a little effort and a good marble polishing compound. Deep etching or large areas will require services of a restoration professional.
3. STAINS
Some stone surfaces can become stained easily if they are not properly sealed. Many foods, drinks, ink, oil and rust can cause stains. Most stains on stone can be removed. For some more difficult stains professional techniques by a stone restoration provider may be the only hope. Permanent stains can occur.
4. EFFLORESCENCE
Efflorescence appears as a white powdery residue on surface of stone. It is a common condition on new stone installations or when stone is exposed to a large quantity of water such as flooding. This powder is a mineral salt from setting bed. To remove efflorescence do not use water. Buff stone with a clean polishing pad or steel wool pad. Stone will continue to efflorescence until it is completely dry. This drying process can take several days to as long as one year. Do not seal stone until all efflorescence is gone.
5. SPALLING, FLAKING AND PITTING
If your stone is developing small pits or small pieces of stone are popping off surface (spalling) then you have a problem. This condition is common on stone exposed to large amounts of water or when de-icing salts are used for ice removal. Like efflorescence, mineral salts are the cause for spalling—and pitting the thickness of a nickel is considered excessive and a restoration contractor will have to grind tile to flatten floor. Instead of salts depositing on surface (efflorescence) they deposit below surface of stone causing pressure within stone, which in turn, causing stone spalls, flakes or pits. Unfortunately, once a stone begins to spall it is almost impossible to repair. It is recommended stone be replaced.
6. YELLOWING
Embedded dirt and grime can give stone a yellow dingy look. Waxes and other coatings can yellow with age and certain stones will naturally yellow with age as a result of oxidation of iron within stone. This is especially problematic with white marbles. If yellowing is caused by dirt or wax build-up, have stone cleaned with an alkaline cleaner or wax stripper. This may be a job best left to professionals. If the yellowing is result of aged stone or iron oxidation, it is not coming out.
7. UNEVEN TILE (LIPPAGE)
Lippage is term given to tiles that are set unevenly. In other words, the edge of one tile is higher than next and is result of poor installation. If lippage is higher than thickness of nickel it is considered excessive and restoration contractor can grind tile to flatten floor.
8. CRACKS AND CHIPS
Cracks in stone can be caused by settling, poor installation, inadequate underlying support or excessive vibration. Chips can result from a bad installation or when heavy object falls on a vulnerable corner. Repairs can be done by a professional stone restoration contractor by filling with color-matched polyester or epoxy.
9. WHITE STUN MARKS
Stun marks appear as white marks on surface of stone and are common in certain types of marble. These stuns are result of tiny explosions inside crystal of stone. Pin-point pressures placed on marble cause these marks. Women’s high heels or blunt pointed instruments are common reasons for stun marks. Stun marks can be difficult to remove. Grinding and/or honing can reduce number of stuns, but some travel through entire thickness of stone.
10. WATER RINGS/SPOTS
Water rings and spots are very common on marble and other natural stone surfaces. They are either areas that have become etched or are created from hard water minerals such as calcium and magnesium that are left behind when water evaporates. To remove either type of these spots, use a marble polishing compound. Moderate to severe etching or larger damaged areas will require professional honing by a stone restoration contractor.