The topic of granite sealers and sealing natural
stone is full of controversy and confusion. One of the main reasons for this is
the fact that most people do not fully understand.
Now, to be fair, many recommendations are
knowingly made based on client expectations and peace of mind rather than a
real need for sealing granite countertops or other natural stone.
On this page, we will do our best to lay out the
whole picture, reasons for or against sealing granite and marble and why, so
you can make an informed decision for yourself.
Myth #1: Marble and granite sealers "prevent"
stains....
Well, sort of, but not exactly. Let us explain. A sealer will only slow down the natural
rate at which a stone absorbs a liquid.
Some stones are so dense (soapstone, many
granites, some marbles, etc.) that liquids just cannot penetrate... or
stain... while others will stain if a spill isn't wiped up immediately. So, a
sealer does not provide an absolutely impenetrable shell (which is the common
perception). It simply gives you more time to clean up the mess before it
stains and keeps the stain near the surface, so it can be more easily removed
if a stain does occur.
Myth #2: A granite sealer is what makes the surface
shiny....
Completely and totally false. The shine or
"polish" on the surface of any stone is created by intense friction
using diamond abrasives. It's a mechanical process and not a chemical one.
However, there are some Chemicals that can temporary darken your stone and, at the same time, provide some protection similar to a Sealer. But the two products should not be confused. A true sealer will not alter the look of your stone.
On a different note, there are some products, particularly acids (like
liquor, vinegar, coffee, sodas) that can damage or essentially remove the polish on
certain calcite based stones like marble, travertine and limestone.
It is a reaction between the calcite and the acid.
It's called "etching" and it's the primary reason such stones
are not recommended for use in high traffic areas. Obviously, etching will not occur on stones with a honed finish.
"Stains" that result
are the clear or lighter colored "water spots" or "glass
rings" that are commonly reported with such stones. But they are not
"stains". Nothing is absorbed into the stone.
It is physical damage to the surface of the
stone. Luckily, most cases of etching are mild to moderate and can be repaired.
However, if severe enough your only option is to call in a professional to
re-polish the surface. And that's the answer to....
