Made a mistake -- washed my slate hearth

[dominick]

Hey guys,

I've had some nasty smells of fireplace residue in the house lately so this past weekend I decided to clean the fireplace. I got a bucket of water, a scrubber, and some TSP and spent an hour or so cleaning the bricks of the fireplace.

It seemed to work well but there was also some staining on the slate hearth as well (the platform in front of the fireplace floor). I decided to try and clean that as well but I noticed pretty quickly that it started to turn an orange color in some spots. Its not everywhere and it isn't terrible looking but it is discolored in one area. I don't know much about fireplaces or the stones that are used but I'm thinking that this slate slab may have had some iron it in which reacted with the water and oxidized, changing the color. Does this sound right to you guys? Is there anything I can do to get the color back to normal or should I learn to love my new multicolored hearth?

Thanks in advance!

 

[begreen]

If it's rust maybe you could do a spot test with a little Extend Rust Neutralizer on it to see it turns black when treated.

 

[Eureka]

Yes there’s ferrous metal content in slate. I used to live in a place with a slate hearth stone and slate bathroom and we used to periodically freshen it up with mineral oil. Really deepens the color and blends in any staining or oxidation. Worked great.