Myrtle Beach, SC find- not sure if shell or fossil?

[Missymeow34]

Hi there!  I am new to not only this group but sea combing/searching for neat stuff.  I was lucky enough to find a fossil sea urchin on my trip this past week to Myrtle Beach.  I also found this.

Initial (and secondary) thoughts had me thinking it was just a shell; however, after some more looking, something told me to hang onto it and look into it.  Does anyone have an idea what it may be (or just a shell)?  Thank you in advance.

Edited April 22, 2023 by Missymeow34

[Al Dente]

It is part of the hinge area from an oyster.