Removing Sulphuric acid stain on granite
Ed. note: For other than acid stains, please see letter 11302, "Remove stains from Granite countertop" for dozens of perspectives on removal of different types of stains.2000
Q. I have spilt 'Black-it Patina Solution' (used for blackening solder) on a 'emerald pearl' polished granite kitchen worktop - and it has caused a white stain on the granite due, I am advised, to the sulphuric acid in the solution. Can anyone please advise me how to remove the stain and restore my kitchen in time for Christmas. I would be very grateful.Theresa K [last name deleted for privacy by Editor]
- Bromley, Kent, England
A. The Acid has reacted with the Granite and etched the surface very slightly. It is quite possible that the damage is minor but the most reasonable method of restoring the surface is by polishing.
Two paths could be taken, first check Granite and Marble suppliers to see if they offer supplies or a service to polish. Second, go to an automotive store and buy rubbing compound and an electric polishing machine (this machine will reduce a few hours of work to several minutes). Then following the instructions with the compound re-polish the counter top. The Granite is quite hard and you have little chance of damaging it further by repolishing.Jaye Waas
- Burbank, California
Thanks, Jaye. I'd agree that the rubbing compound brings little risk -- except that removing some stone while still leaving a flat surface isn't dead easy as anyone who has sanded a floor has discovered :-)
I think the repolishing of the stone may be a job for a professional, or at least someone experienced with it. Trial and error learning on your countertop doesn't sound promising at all :-(
Ted Mooney, P.E.
Pine Beach, New Jersey
Granite counter damaged by cleaner containing citric acid(2002)
Q. I have a granite bathroom counter top of Madura beige (light-colored) granite. The stone directly around the sink has turned dark, I think due to using a common bathroom cleaner in the sink that contained citric acid, which probably came in contact with the counter while wiping down the area. The darkness makes the granite look permanently wet, even though it is not. Is there anything I can do to restore the original look.Susan Andrew
- Wilmington, Massachusetts
February 18, 2008
Q. Zap [linked by editor to product info at Amazon] spilled over under my sink on a soft cloth and my housekeeper proceed to wipe down my granite counter top and my oven, micro wave doors. It was so strong it removed the name (GE) from my micro wave doors. How can I remove the streaks from these surfaces? HELP!SANDIE OBALLE
housewife - San Bruno, California
July 9, 2008
Yes, I did it... I know it says not to but I used it around my faucets on my granite counter tops and now there is a cloudy white mark all around my faucets. is there anything I can do to fix my granite counter tops?
homeowner - Birmingham, Alabama
September 7, 2016
Q. How can I remove a white stain off my granite countertop?
My husband accidentally spilled some acid to clean the rims on the granite and it turned white. What should I do to restore the shiny look (granite original color is brown and black).
- Houston, Texas
September 13, 2016
A. Time to review the difference between residue and etching.
Residue is when a foreign material has dried on the surface. Typically you just need to re-wet the material with an appropriate solvent (possibilities include water, soapy water, acetone, rubbing alcohol, etc.) and then wipe it up.
Etching is when the foreign material has eaten away some of the surface. This can change the texture and/or chemical make-up of the affected areas, which changes the appearance to the naked eye. Shiny surfaces are generally shiny because they have been polished with fine abrasives to a high level of smoothness. Think of it like how a wood surface is sanded until it is very smooth. Etching is like un-polishing, it increases the roughness. Think of that like bashing your smooth wood in with some pointy metal things, like a meat tenderizer mallet. The only way to get that wood smooth again is to sand it down all over again.
Acid on stone? Almost certainly etching.
Stellar Solutions, Inc.
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