Some stone counters are porous and need to be sealed. We seal the stone counters that we install, but sealer does not last forever. We really cannot tell you how long the sealer will last because that is determined by how you treat your counters.
The best thing to clean your counters with is just dish soap and water.
If you use anything acidic it will break down the sealer.
Do not use 409 or Windex to clean your counters or your sealer will not last 2 months.
Natural acids will also break down the sealer, such as orange or lemon juice. The sealer gives you the ability to clean up spills. If you get orange or lemon juice on the counter and clean it up within a reasonable amount of time (an hour) it will not damage the sealer. If it sits all day on the counter it will work its way through the sealer and break down the sealer. The same is true with coke products and oils.
If you use mild cleaners to clean your counter the sealer should last for years.
If you notice water making the counter darker, then it is time to reseal the counter.
This is a very easy thing to do.
Purchase a penetrating sealer, readily available at Home Depot, and make sure your counters are clean.
Then spread the sealer evenly around on your counters.
Let it sit a few minutes, and then wipe off any excess.
You repeat this until the counter will not absorb any more.
If you have any additional questions please feel free to call our office 615-441-9991.