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Cleaning hardwater deposits from slate shower

Article Number: 318 | Rating: 1/5 from 1 votes | Last Updated: Tue, Aug 14, 2007 at 12:00 AM

My husband installed beautiful slate in our shower. He put some kind of shiner on it and sealed it as well, but now our hardwater has left white haze. I'm assuming grocery store cleaners would be too harsh and would eat away at the sealant, but we've already tried a stone cleaner without any positive results. What can I do?

Dear Krystal:

Assuming that what you have are indeed hard mineral deposit, a specific product like MB-3 should do the trick for you. However I must bring up a few points:

1. By saying slate you're saying very little – if anything at all. There are many different (and I do mean different) kinds of slate that span from dense and (almost) acceptable rocks, to slate that will actually fall apart under running water, and everything in between. So which slate do you have? Because of this widespread specific ignorance about stone, IMO based upon the countless complaints I receive every day of the week, slate in general does not belong in a shower stall.

2. All this indiscrimate application of massif doses of sealers to stone in a wet environment is only conducive to all sorts of bad surprises. Mankind should master nature by understanding, not by forced. By literally suffocating a stone installed in a wet environmen you're certainly not doing that. Not to mention that you may have applied all those sealer way too early in the game. If one must seal stone in a wet environmnet, one should wait for at least a couple of weeks before doing that in order to allow the moisture of the setting material to cure properly without being slowed down or stopped altogether by some useless sealer.

3. All that said, it is possible that your hard water deposits are just not that, but the formation of efflorescence from within the stone due to either the improper specification of the particular slate that was selected, or the presence of all the sealers applied to it, or a combination of both.

If it is mineral deposit (and after all it could be), MB-3 will tell you for sure. If not... :-(

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,

Maurizio Bertoli

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