5
$\begingroup$

enter image description here

I found this rock by the shore of Lake Ontario. It's light weight and it was grouped with some other rocks with the same patterns.

$\endgroup$
8
$\begingroup$

Your rock contains crinoid stem fossils.

Wikipedia has a good summary of crinoids

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.