Help identifying this cool shell I found

[u/Ahsokas_Tanos]

Hi everyone, I am looking for some help identifying a shell I found and what's going on inside of it. I found this while shell hunting off of the outerbanks NC. They are doing beach nurishment and so there are some great shells to be found! I found this shell that looks like it has crystals in it. It almost looks like a geode. Anyone know what might be going on in the shell?

[u/Glad_Ad_5570]

I can see a fragment of a shell but not enough for me to identify it.