I Need A Rock ID

I dug up these rocks at my Aunt and Uncles house today. These rocks were found in Pennsylvania, near Pittsburgh. I did the vinegar test on them and didn't see any bubbling. The problem that I have is that I don't know what they are and if they are aquarium safe. They look like slate or shale and some of them have rusty looking marks (Photo 1).

 

Probably some iron content, which wouldn't be a huge deal, unless there's a lot of iron in it.
The only other concern I'd have would be if it were the type of shale that has oil in it. Problem is, I have no idea how to test for this. Sorry.

 

Looks like shale to me does it break pretty easy. if its harder I would say slate.

 

Probably some iron content, which wouldn't be a huge deal, unless there's a lot of iron in it.
The only other concern I'd have would be if it were the type of shale that has oil in it. Problem is, I have no idea how to test for this. Sorry.

Thanks for you quick response! I just researched oil shale and found that there is an oil shale reserve in Pennsylvania so it is possible that it contains oil. I also found out that oil shale is known as "the rock that burns." Perhaps I can try to burn it to determine if it contains oil?

Looks like shale to me does it break pretty easy. if its harder I would say slate.

Thanks for your response! It does break easily so I am pretty sure it is shale. Now to figure out if it contains oil...

 

If you want to test for high iron or oil in the rocks bake them at 200 for 2 hours than let cool them broil them in water for 2 hours and than let them cool than put them in a rubber maid container with water and let them sit for 2 days and if in 2 days no oil film shows up they should be safe to use in the tank.

 

If you want to test for high iron or oil in the rocks bake them at 200 for 2 hours than let cool them broil them in water for 2 hours and than let them cool than put them in a rubber maid container with water and let them sit for 2 days and if in 2 days no oil film shows up they should be safe to use in the tank.

Awesome! I will try that as soon as I get home. I will just soak them for now. Thanks!

 

not sure about in aquariums but in the wild you will find many fish hiding under shale ledges and frogs hoping along it. I'm from NE OH and spent lots of time growing up hiking and camping in the woods

 

If you want to test for high iron or oil in the rocks bake them at 200 for 2 hours than let cool them broil them in water for 2 hours and than let them cool than put them in a rubber maid container with water and let them sit for 2 days and if in 2 days no oil film shows up they should be safe to use in the tank.

I would worry about heating shale dryer it gets the easier it seems to break and crumble. Shale is basically just a mud rock.

Great for finding fossils in. did you get so lucky with your rocks?

 

I would worry about heating shale dryer it gets the easier it seems to break and crumble. Shale is basically just a mud rock.

Great for finding fossils in. did you get so lucky with your rocks?

I didn't find any fossils in my rocks. I don't have any experience with heating rocks of any kind so I don't know how the shale would react. Maybe just soaking them will extract the oil?