I have some geodes that I found an I broke open myself, I also got a rock called larimite, it is the one with the blue color, i bought it in the Dominican republic. The other two are from mammoth cave. How can I post a picture of them? And are they safe?

There is an "insert image" icon right above where you are typing. 2nd from right; yellow box w/ mountains

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You should be fine, I use them in my tanks as well as petrified wood and haven't seen any problems. Just make sure you srcub them real good and maybe soak then test the water to see if they are leaching any unwanted minerals if you are worried. I like the petrified wood because I believe it helps to soften the water naturally and its pretty.

Do they pass the vinegar test?

I dunno, those top ones look suspect, I'd def. hit them with vinegar and see what happens. If they fizz they'll most likey jack up ph.

I sprayed them with vinegar, and the blue one fizzed up, but the other one just sat there