Sealing your granite worktops can help protect it against a variety types of stains. There is no sealer that can make your worktops completely immune to stains but it will significantly slow down and inhibit the penetration of substances so that you have a chance to clean up before stains leave their mark.
Before sealing any granite worktop, you should test the absorbency with some water. Wet a part of the surface with a few drops of water and check again after 10 to 15 minutes. If the water is penetrating the granite, it’s time to seal. There is no point in sealing a worktop that does not need it! Sealer needs to penetrate the granite so, if your surface is already stain resistant, the sealer will do nothing more than remain on the surface and make your worktops look cloudy.
Select a sealer and make sure that it is suitable for use on granite. For the best advice, ask granite and natural stone specialists. Some products are more expensive because they are superior in quality and yield better results.
Clean the worktop and allow to dry for at least 8 hours with plenty of air circulation. Wear gloves, make sure the room is well ventilated and test the sealer on a small area first. If you are happy with the results, apply the sealer evenly to the entire surface and allow to absorb. Apply a second layer if necessary and, when finished, wipe excess sealer off the surface as per label instructions. Do not use your worktops for at least 48 hours to allow the sealer to really set.