What is this!?

Anyone know what this is? Other than a deformed shell, haha!
Found it by the ocean and it is kind of heavy more than the usual shells around here and it is not a rock.

How do they get like this? Is it «normal»? (I should maybe use the world «regular» cause I don’t like normal.)

My favorite place for hicking and I’ve been walking multible times a day for years but never found something like this before.🧐

And steemit turned all my photos oposite way this time. 🙄

But seriously what is this?! 🧐
And no I don’t think it is «gold» or anything valuble I just think it is super interesting.