Not Sure What I Found

[Spanky312]

I found this and thought it was part of a scallop until I looked inside. It looks similar to the inside of a fossilized sand dollar. What is it??? I know the one photo attempting to show the inside is blurry but it's the best I could do.

[Al Dente]

It's the hypural from a tuna or bonito. These are commonly called fish tails.

[Spanky312]

Gosh I feel dumb! When I look at it now it looks exactly like a fish tail. Thanks!