What is this?

Not a clue, but I'll take several, please...
 
KY has some crazy stuff going on down there lol. But that is some cool rock.
 
that is a nice looking rock. I'm in the northern part of ky and never seen anything like that. I agree there are a lot of wierd rocks around here.
 
rock

OK, It is definitely limestone. My brothers friend is a geologist and said it was limestone that was shaped by water millions of years ago! I have looked everywhere and can't find any trace of there being holey limestone in the state of KY. Next time I go i will take pics and post them so all of you can see how much of this stuff there is. also does anyone know a way to get all the brown residue off of it? l
 
I think the brown color gives it much of its appeal. On a serious note, if it is limestone and you use it in your aquarium be ready for some very high pH uncontrolled by you. Not sure how high because I have never owned a high pH test kit but from experience I can tell you it will be off the high end of a normal pH test. Ground up limestone is what farmers use when their soil is too acid for their crops. It brings the soil pH up very nicely and does not need to be applied again for years. Might be OK for african chiclids but you need to check with somebody who understands africans. I would test it in some water for a few days and see if you want to go where it drives the pH.
 
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