Black granite

I am working on a project, we have rough black "granite" tiles on the stairs and walk ways. We started out doing a construction clean, and following someones advice we used muriatic acid to clean the stone, diluted 10:1. We have also used a tile and stone deep cleaner. both of these seemed to work somewhat, but left, what seems to be residue on the stone. What is the proper way to clean this kind of stone. I was told that the correct color is a dark grayish look, rather than the dark black on this stone.

 

Dear Michael:

By your description is hard to tell what happened and what the best course of action should be. But I'll try to guess.

I highly doubt that, no matter what you did to that stone, there's any residue sitting on it. No cleaner - acidic or alkaline - leaves any residue that couldn't be easily removed by rinsing it.

What you probably see could be residue of a color enhancere that may have been originally applied to that stone and that was damaged by your cleaning.

In fact, you're right: that stone should look gray (not even dark gray - just gray) in its natural state. If it looked black before you started the cleaning, I have to assume that a color enhancer was applied to it.

IF that is the case, then some further heavy-duty cleaning using the same stuff you used, may accomplish the task of removing every residue of the color enhancer. But it's not going to be easy, and there's no guarantee, I can tell you that!

Maybe the best course of action could be to apply some more color enhancer to the stone (like MB-6) and make it turn uniformly black. That should be much easier.

To find out if such procedure could work, try with some baby oil. What the baby oil will visually deliver on a temporarily basis, a color enhancer like MB-6 will deliver the same look permanently.

 

May I ask you now to please read and e-sign our Statement of Purpose at: http://www.marblecleaning.org/purpose.htm?   :-)

Ciao and good luck,

Mauri z io Bertoli

 

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