How do you clean efflorscence off of newly sealed slate flooring?

Image taken on 2009-06-19 11:08:12 by Bryn Pinzgauer.
We just tiled the kitchen with natural slate and then sealed the tile and grout with special sealer, specifically for slate floors. About a week later, I am now noticing that 2 dark tiles have white “stains” on them, looks like they are in the tile because I have tried my slate cleaner and it goes away when wet but when it dries, the white discoloration is back. Any suggestions on how to get rid of this? Thanks for your help.
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December 2nd, 2009 at 7:11 am
have you seen those white cleaning pads, i don’t know who makes them but there white and rectangular. you can get them at any store that has household cleaning stuff..that should work.