shale

[mrChimps]

I wanted some dark rocks to put in my malawi tank, and think i may have uncovered som shale in my back yard, several large peices all quite light for their size.

Does anyone know how to tell if it is shale & if it is ok for a home aquarium (after being stood in boiling water)?

thanks in advance, mrChimps

 

[Gumby7]

A long time ago I lived in a place with shale beds. Its basically mud that has turned to sedimentary rock. It is relatively soft, black, layered and only flakes off in small pieces (up to 2"). Depending on the deposit it tends to be in wavy layers something like sand underwater at the beach (imagine that!).

As you can see it is quite different than slate which is quite hard and very flat.

I see no reason why you couldn't use it in your tank if you can collect decent pieces. You may even find a fossilized trilobite!

Gumby