Seth-spills should not be darkening. I had the opposite effect where, because the stone is so dense-the sealer actually laid on top, creating rough areas where there was too much. They came back to scrape off the excess and wipe down with acetone. I was afraid all the sealer was off, but he did a water test where he let the water lay overnight. it was still in a puddle the next morning-it never darkened. The stone is not porous like you mentioned. It is the opposite. It is very dense and strong. Stronger than granite. That is why it is so hard to cut through and they hate templating it.You might want to go to stone Tech's website, I use their cleaners. They sell a stain remover. It's in a samll can, it's a paste u put on and it lifts up stans. It is safe for all stones. I used it on my old kitchen granite for an oil stain- it worked. I would also have them come back. Wipe down with acetone and apply dupon't proffesional solvent based sealer. Sounds like they used a water based on yours. Water should always bead off, not darken. Hope this helps. Good luck-kitchen looks great! Michelle
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