Sealers, when properly selected and used, can be extremely beneficial in the protection, ongoing maintenance and longevity of a stone installation.
The primary function of a stone sealer is to provide stain resistance to a porous stone. To best understand the realistic expectations of stone sealers, the operative word "resistance" should be viewed in terms of "reaction time." There are many sealers available today, yet none make the claim of being "stain proof." What sealers will provide is "time to react," meaning a period of time that the sealer will hold out the contaminant, allowing easy removal from the stone surface before there is stain penetration. Based on the quality of the sealer used and the type of contaminants the stone is exposed to, reaction time will range from mere moments to many hours. The primary distinction between today's penetrating (impregnator-type) sealers is the reaction time they provide and the range of contaminants they resist.