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(The Fundamentals of the “Sealing Cult.”)

An article by Maurizio Bertoli, the founder of the “marble cleaning” company

I was talking with a couple of stone yard and they both told me that “they seal each and every granite they fabricate and install” They sounded very proud of it, too!“All granite need to be sealed, or else!…”“My fabricator told us that if we would not let them seal our granite countertop, we’re gonna have to sign a waver by which we give up every warranty they offer on their products!”And so on … I’ll tell you: it has become almost a religious cult: The “Sealing Cult!”The possible voiding of the warranty is simply amazing – not to mention outright illegal! I mean, are they going to refuse to replace your countertop if it cracks within a couple of weeks after installation because you refused to have a stupid impregnator/sealer applied to it??!What is a sealer for stone anyway, including our very own?

Sealers for stone (a.k.a. impregnators) are below-surface penetrating sealers, not topical hard-shell sealers like those, for instance, that are applied onto wood floors or furniture.

They are delivered inside the stone by natural absorption. The solid part of the sealer (a resin of sorts) will stay in, thus clogging the pores of the stone, while the carrier (solvent or water) will evaporate. As the most important phase of the whole sealing process, every residue of the product will have to be thoroughly removed from the stone surface. Therefore, no alteration to the color or the finish of the stone surface will ever occur. It’s also intuitive that an impregnator can’t – and in fact doesn’t – offer any protection whatsoever to the surface of the stone.

It should be pretty clear at this point, that to work an impregnator must go in the stone; but to do that, it has to be absorbed by it. Several commercial granites don’t absorb anything, due to their inherent density; therefore no impregnator will ever go in. If you apply it regardless, there’s the distinct possibility that some of it will remain in some kind of “limbo,” and, if it so happens to be one of those impregnators that are sensitive to pH active liquids, will get damaged by spills, giving the impression that the stone is damaged! Such damages will appear in the form of “ghost water stains” or “water rings.” At that point, the contractor who applied the impregnator at any cost (just because the “salesmen” told him to do so) will not know what he’s looking at when you’ll call him back with your problem. Thus he will try all sorts of stupid wizardries, which will amount to nothing! And your mysterious ghost stains will stay there forever driving you nuts! If instead the impregnator is one of those that are not sensitive to pH active liquids, then nothing would happen, but it would still represent a total waste of time and money. Impregnator/sealers are not cheap!

What’s also funny is the spin-off of this “sealing cult”: in fact they are all overly concerned about the sealer thing, but at the same time don’t give a second thought about the much more important issue of the daily care!

If the stone needs to be sealed, it has to be done once every few years. But people have to clean their countertops every day! If they use some generic cleaning product or some home-brewed concoction, they will run the risk of damaging the stone and/or the sealer!

No wonder there’s room for such manmade materials as engineered stone (quartz-based slab, such as Silestone ™, Ceasarstone ™, etc.) and solid surfaces (translation: solid plastic; such as Corian ™ and the likes) that sell for more or less the same price as granite. The horror stories stemming from the “sealing cult” (translation: Ignorance) scare people off from the most suitable and beautiful material that money can buy for a countertop, and send them find refuge in the reassuring open arms of the “salesmen” touting the wondrous virtues of the “anti-granite”!

As it often happens in life, “We found the enemy: it’s us!!”

And the show goes on!

Maurizio Bertoli