FMF - Friends of Minerals Forum, discussion and message board

[Kales83]

Hello,
We live in central Alberta, Canada.
I don’t believe we found anything fancy, but thought this rock was kind of cool.
Can anyone tell me how it got like this, and that I don’t have a piece of petrified cat poop on my kitchen counter? 😭

[Kales83]

Here is another photo.

[SteveB]

It's a porphyry. Google porphyry formation to learn how it forms. Porphyry are very common and interesting to look at.

[Riccardo Modanesi]

Hi to everybody!
Kales, have you tried to drop some chloridric acid on the rock, and particularly on any of the white crystals on it? Does it fizz?
Greetings from Italy by Riccardo.

[Pete Richards]

In the context of a porphyry (or perhaps better a vesicular basalt or other rock), the elongation of the white structures bothers me.

An alternative explanation of this object is that it is a fossil of a branching colonial coral in a dark-colored sedimentary rock. Better close-up pictures, information about the local rock formations, and perhaps some chemical tests (e.g. the hydrochloric (muriatic) acid test suggested by Riccardo, but to test the black matrix as well as the white tubes) would be helpful in sorting this out.