It's a rock that's been holed by boring clams: https://carnegiemnh.org/not-boring-clams/
If you want to know what kind or rock it is, I can't help you there.
Let us help you identify that mysterious object you’ve found.
Currently in CHALLENGE mode: If you've got something obscure knocking about, post a picture, and let's see how we do. Please prefix such posts with "CHALLENGE:" so we know we've got a fighting chance.
It's a rock that's been holed by boring clams: https://carnegiemnh.org/not-boring-clams/
If you want to know what kind or rock it is, I can't help you there.
It looks like an igneous rock or a rock that was formed through the cooling of magma
Looks like a rock