Bought these copper pans from the charity shop, what's inside them?

Hi there,

So today I saw these copper pans at my local charity shop and really liked the look of them. They have the stamp Apiol - Made in Portugal on the bottom.

Anyway my question is, what are these pans lined with, how do I clean them, and are they safe to cook with?

I've put a couple of photos below, as you can see I've cleaned the smaller one up with some ketchup on the outside and its come up 10x better, however is showing a copper finish of the bolts on the inside of the pan, is this ok?

A couple of the bigger pans I haven't cleaned yet, and have some black marks on the inside, as well as some scratching.

Any insight to what I've acquired and how to clean/use them would be great.

Thanks in advance!
Danny