How many coats of the sealer do you need to seal it!? Seems like I have put on 5 coats and water still shows spots!

It's not to be unexpected for the marble to darken when wet, even when a sealer is applied. Sealers are designed to let water pass through, their only intent is to give you an extended opportunity to clean up something that could potentially cause a stain. Penetrating sealers, by there very name, are supposed to be just below or at surface level, filling any micro pore on the stone. The polishing process alone creates such a high surface tension that your stone will not absorb much sealer to begin with. The quality of the sealer also has a lot to do with it. You don't get much quality in any sealer that runs less than $75-$100/gallon. I did explain the difference between cheap and expensive sealers in response to a sealed grout question similar to yours about 6 months ago. I copied it to post below. I didn't change it around for the sake of it being used on stone, but the gist of it is the same. You can read it if you want, or, just go enjoy your new stone...


Grout sealers are not intended to make grout waterproof, only to help in preventing staining substances from penetrating the grout. Their ability to prevent stains is more like a small buffer to allow an opportunity to get the staining agent cleaned up, but if left on the grout, it can often cause a stain anyway.

Sealers are a base into which solids are solvent and when the sealer is applied to the grout, the solvent evaporates away, leaving the solids in the small pores of the grout. This is an over generalization, but for the sake of explanation, it works. A more expensive sealer has many different sizes of solids. Imagine a 5 gallon bucket and you fill it with some big rocks. Full, right? Well what if you then throw some pea gravel in there? Oh, lots more room than you thought, filling in all that space between the bigger rocks, huh? Seems full, but now it will still fit sand. Cheap sealers are like the bucket of large rocks, expensive sealers are like the buckets with rocks, gravel course sand and quarry dust. No matter how you packed the bucket, they will both let water pass through though, and sealers are specifically designed to allow moisture to pass, though it will obviously take much more water to penetrate as deeply into the later bucket. If your grout darkens after it's been sealed, it's not to be unexpected.

You could ask the cleaning/resealing person which exact sealer they used. No matter how many coats of cr@ppy sealer they use, you'll never get the kind of protection you wish for.

Hmmm... Thanks for that. I had no idea that it worked like that. I assumed it would "seal" it up tight. I guess I will just make sure that the wife is careful with makeup etc.

THANKS!