Does slate rust?

[jb-ny]

I got some slate tiles from Home Depot and made some caves.
This morning I noticed two pieces had what looked like rust on them.
Has anyone experienced a similar problem.
This can't be rust, can it?

 

[inkyjenn]

it would indeed be iron oxide.

 

[Hooked Newbie]

Slate itself will not rust. It may have a vein of metal in it however or been stored against metal.

 

[jb-ny]

I removed the two pieces.
should the rest of the slate be removed?

 

[Hooked Newbie]

Probably better to remove it all and play it safe. You could place it in a bucket of water for a couple weeks to see if any problems emerge.

 

[rocker92]

x2

 

[Nolapete]

Get some strong acid, follow directions, and pour over the slate. Anything not inert will react with the acid. Good test to see if rocks are aquarium safe.

 

[SuBXeRo]

cant you just use vinegar? Some slate does have iron in it, black slate doesnt most of the time from what i have seen, but other color schemes do include it. this is what the lady at the tile place told me

 

[SuBXeRo]

i asked this question in flash chat and some of the responses i got were comforting. if the slate does rust, iron may get into the water but if your a planted tank, the plants would love it. others said they have slate that has rusted and the stock has been fine. u more want to worry about limestone or stuff that will screw with the ph. careful monitoring is a must when dealing with new unknown things

 

[yourchoice]

I have used the Home Depot 12x12 untreated tiles.,Pick the ones that didn`t have any rust colour in them.