How do stone sealers work?
The most important thing to know about sealer is that they do not sit on top of the stone. The impregnating sealer that we use is absorbed by the stone. That being said most granite and many darker marbles are so dense they will not absorb sealer at all!
Do stone sealers prevent damage?
The other important thing to know about sealers is that they only protect against staining. Etching and scratching, the most common problems with marble and natural stone, are NOT protected by sealers!! Often we get clients who want us to reseal their granite counter tops. The problem is that the sealer just sits on the surface and actually attracts dirt and food residue. It can make your counters appear “smudgy”.
Is my stone easy to seal?
Here is a good test to see if your stone is a candidate for sealers. Drop a bit of water on the surface and let it dwell for 5 minutes, then wipe it up. If the area where the water was appears darker (it will evaporate with time) then it means some of the water absorbed and as such is a candidate for a good quality impregnating sealer. If not then don’t bother with sealer!
Should I seal grout?
There is one area where sealer is helpful and that is on grout lines. Once we have cleaned a floor or shower we will apply a sealer to the grout lines to keep dirt and bacteria out. New grout comes with a built in sealer, so if you have us re-grout something, you won’t need sealer there either.
What are stone coatings?
The other option for treating your stone is a coating. There are several products available for counters like Clearstone which we have mentioned in several other posts. Clearstone is a coating which sits on the surface of the stone, it is NOT absorbed. It is a great solution for softer and lighter marble and stone that is prone to staining and etching.
Read more about the history of sealers at :