One of the major worries about granite that homeowners have is about sealing. This is definitely an important consideration and should be clearly understood.
Most granite is porous to a certain degree and thus susceptible to staining. Staining can be easily controlled by application of a sealer on these surfaces.
Many granites do NOT need sealing. Darker colors like Uba Tuba granite, Blue Pearl granite, Absolute Black, Black Galaxy or Baltic Brown granite (and many others) are so dense they simply will not stain and thus do not need sealing.
These super-dense varieties of granite are without question the very best countertop surfaces available. In some cases a sealer could be applied. A simple water test is all that's required to check absorbency and determine if and when sealing granite countertops is necessary (or not).
We highly recommend using Permanent Sealer or one of these impregnating sealers when testing shows it would be beneficial.