Sold me limestone! Not limestone! What is it?

[lucky777]

Went to local rock and brick guy. Asked for limestone, he said it was. Looks like slate to me. Do vinegar test and no fizzing? The pink tones are from the camera, not the rock.

Is it slate? I thought it was usually darker. I'll still us it if it is slate, just trying to make sure. Tested with acid and it didn't fizz at all.

Any help would be appreciated!!

Better pics

[JetJumper]

That looks like granite to me.

[lucky777]

sorry had changed pics

[Nerine]

shale ?

[bitterman]

It is sandstone. That is what they put on my parents house.

[Fishnut]

Slate is very fragile.  What happens when you drop a piece on it's end on a hard surface, like a paved driveway?

Kinda looks like slate but a bit different.  Not limestone though.  That's a more white/cream colour most of the time.

[dpatte]

I believe its shale, which , if its local, should be fine for your aquarium.
Shale has sedimentaty lines (layers) and often splits along the layers.  It may also have fossils.

Slate is harder and generally shows no layers.

Granite is even harder and has no layers as it is not sedimentary.

[exv152]

The area I live in has tons of limestone, we live near an ancient limstone kiln, and that kind of looks like some of the limestone you would find here in the ground. I would try submerging some in a bucket of water. Test the pH before adding the stone, then again like 24 hours later to see if it goes up.

[dpatte]

sandstone has sand-sized grains in it. shale, though, is made of old compressed mud. Both have layers and should be fine for your tank.

Limestone is compressed chalk and will dissolve over time. you can test: if it foams with vinegar, then don't use it.