Does Granite have to be sealed?
That is a bit of a challenging question. Does it HAVE to be sealed, probably not. Is it a good idea to seal it, the answer is Yes. Granite in and of itself is dense enough that it will resist most stains without a sealer being applied, but to make sure you are as safe as you can be with your stone you should apply a sealer. All natural stones have a minute amount of porosity. The sealers will help combat that porosity by filling the tiny pores that may be in the stone.