There are endless threads discussing the porosity of quartzite, but it seems there is consensus that dolomite tends to be porous across the board whereas some quartzite (Taj Mahal, Sea Pearl, White Pearl and some others) are considered non-porous - or at least there are no complaints on those particular stones as it relates to porosity. Bianco superiore, mont blanc, levezzi, luce di luna and others are hit and miss and success has been mentioned with good sealing. However, what is one to do to prove a particular stone in a surface warehouse that is labeled quartzite is actually quartzite? We have found a lovely slab of Fantasy Lux quartzite and all I can find online agrees that it is quartzite. It is a very light color with some deep gray/blue veining - which does concern me a little with with many stones with those aesthetics seem to have porosity issues, but the larger issue for us would be spending the $$$ for a quartzite, but really being sold a dolomite. What can I do to prove we would be purchasing a quartzite over a dolomite? I don't know of a way to do a glass cutting test as the edges are covered. Any advice or experience with this particular stone?