jcardona1;4552542; said:Slate will literally 'rust' if it's submerged. Just a quick rinse is fine. I used black marble and it looked sweet!
jcardona1;4552562; said:Guess it depends on the source. Slate sold at many home improvement stores isn't really slate. I've read it's various types of ground up stone, some of which contains iron. That in turn oxides when left under water. I've even seen slate tiles out of water have some orange rusting to them.