Dear Jane:

I really don't know if I have to laugh or cry hearing your report about the idea that tiles are made more durable than slabs because they have to go under foot traffic!!!!!... As if it were possible to make tiles of a certain stone harder than the their slab counterpart!!!

Is there any limit to specific ignorance about stone displayed by certain stone industry operators?!...

That being said, your extensive “water staining” seems to be a clear case of malicious stone doctoring, which is a criminal activity infringing the consumer protection act.

Black “granite”, whether tiles or slab, is not supposed to “water stain” at all – ever at all!

If I were you I would demand your “knowledgeable” installer to replace your tiles at no charge, or else.

Of course, if you only complain and take it in the chin without reacting, this is not the place for you. We're here to help people, at no charge, who want to see their rights protected; but, without meaning to be rude, we have no time for quitters.