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Stains on Premium Black Granite Kitchen Countertop

We recently purchased Premium Black Granite for our Kitchen. They installed it and a week later we noticed cup rings (simple water rings) on certain areas. The company sent out people to clean it with Acetone and that did not work. They then sent out another team and they tried the same thing, tried a blowtourch to losen it and then finally put on Ager Color Enhancer Sealer Tennax and it cleaned it all up. After reading numerous postings on your site about "shoe shine" procedures and other methods and that true granite cannot be sealed and does not need to be, I am concerned that this was just a cover up and that the issue will happen again. Should I wait to see if we get stains again or start legal action to have them replace it? I feel uneasy and am unsure what to do? Thanks.
 

Dear Scott:

It could indeed be a case of maliciously doctored “black granite” (I love it when they call it “premium”!...), but before you go all out with your demands, we have to find out what the real story is.

So, first read this:

 

“Let's start by saying that when one mentions Black “Granite” one's talking about a huge variety of stones coming a little bit from all over the planet, each and every one of them not geological granite by a long shot, and each and every one of them with different characteristics. If that wasn't confusing enough, each and every one of them are processed with even if so slightly methods – which again can make a difference.

There used to be three possibilities to explain the problems that you are experiencing, which are here listed in order of probability (the first being the most probable):

 

  1. The fabricator applied an impregnator/sealer to it believing that it's granite. No impregnator/sealer will ever be absorbed by black “granite” due to its inherent high-density; therefore it won't do the first thing about doing what's designed to do, which is prevent stains. (What you have are NOT stains, and no impregnator/sealer on the planet can prevent those.) Many a sealer turn out to be sensitive to acids; hence the “mysterious etching.” Not on the stone, rather on the sealer that had no business being there.
  2. The slab had been “doctored” by the factory by applying some sort of black shoe shine in order to make it “blacker” and, therefore more “sellable.” After a while the “shoe shine” will begin etching as it gets eaten away by acidic liquids. The true color of the stone is dark gray.
  3. It is one of those as-rare-as-a-white-fly “mutt” stones with some acid-sensitive minerals in it. In this case it is actually the stone that gets etched.

 

In the last couple of years there's been a change in the scenario above. Another possibility has entered the scene:

 

  1. Certain manufacturers apply some sort of protective wax to the slabs. It is not actual “doctoring,” since there's no alteration to the color of the stone, but the result is the same as if the slab had been “doctored” with the “shoe-shine.”

 

Finally, case 3 above is not as rare as it used to be anymore. At least a couple of “Black Absolute Granites” allegedly from India and China entered the scene recently and are terrible “mutt” stones. Since they are cheap (to the importers) they push them like cra zy at full black absolute granite prices.

 

Having said all that, the remedy to the points 1, 2 and 4 is to remove whatever it is that's sitting on the stone surface, by either stripping it chemically by soaking it with a solution of water and phosphoric acid, or mechanically, by rubbing on the stone surface a polishing compound for marble (NOT for granite!) with a little bit of water.

Case 3 is terminal. It can be fixed professionally, of course, but it can't be prevented. Basically, the granite that's not granite is behaving like marble.

 

From a legal stand, cases 2 and 3 are full-fledged consumer fraud and could (and should) be prosecuted legally.

 

All things considered, black “granite” – which should be considered among the most enjoyable materials as a kitchen countertop – has made it out my own list of recommended stones.

Until the industry will not straighten its act up by becoming serious about the classification of all the different “granites” on the marketplace and dictate strict rules and guidelines about their characteristics and implied guarantees to the consumers, my position is going to be that from now on.”

 

Now, the fact that they “solved” the problem with another doctoring agent is mighty suspicious and certainly not acceptable as a real solution. (Black “granite” must be black on its own, not because it was color-enhanced.) This “solution” also clearly points in the direction of either case 2 or 3. Although case 1 could not be entirely dismissed (but I would be extremely surprised if it turns out to be the case), I would take case 4 out of the possibilities entirely: a product like Ager would have made a mess out of it.

Now you have to push the issue and you must try to “stain” again your countertop. Don't be hesitant or afraid: if you won't do it now it will happen in the (not to far) future anyway (unless, of course, you will stop using your kitchen altogether). So you might as well take the bull by the horn and get done with it. If the stone is sound (as it should be), nothing will happen if you execute my following directions, and you will know that most likely you will never have any problem from now on. So do this: spill a couple of teaspoons of white vinegar (or red vinegar – it doesn't matter) in the middle of your countertop. Let it sit for 1 minute or so and then wipe it dry. If the surface is still unscathed, you're good.

If not…

There are two possibilities:

 

1.     You have a lighter discoloration, but the surface of the stone where it is discolored is still nice and shiny. That would be the sure sign of maliciously doctored stone.

2.     The lighter discoloration appears detectably duller than the rest of the surface of the stone. That would point toward possibility 4, which means that the stone is “mutt” and contain acid-sensitive minerals, which in turn disqualifies that stone from being sold as mercantile granite.

 

Report your finding to me and send me pictures. In the meantime, pay a visit to: http://www.doctoredstone.org, which is an offspring of marblecleaning.org. In there we will also be able to read the Chapter on the subject of stone doctoring (with pictures and all) from my 430 + page book on stone maintenance and restoration.

 

And remember you can help! As a consumer of stone you're the best qualified to make things happen! Will you now please read and sign our Statement of Purpose by logging on at: http://www.marblecleaning.org/purpose.htm? By spreading the word about this valuable site among your friend & family and the stone trades' people you've been dealing with, you will be rendering everybody a valuable service!

Thank you.

Ciao and good luck,

Mauri zio Bertoli

 

www.marblecleaning.org – The Only Consumers' Portal to the Stone Industry Establishment!
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