beachcombing

I found this at the beach today and I can't figure out if it used to be part of something, is a fossil, or is just a uniquely shaped rock! It has a smooth curve, and the backside has a bit of a lip or ledge on it. Any guesses? Thanks!

Hi, just wondering if anyone knows what this object is? It seems to have some sort of trademark on it and made of clay or something. Not sure what way the symbol is meant to be. Thanks in advance.