Isle of Man 1798 George III 1/2 penny Confusion!

Hi everyone! My first post here so please be gentle :)

I am only just getting into coin collecting and have found myself a little confused by the coin in the attached pic. Numista have this coin listed here: https://en.numista.com/catalogue/pieces18463.html and it states it is copper. However, I have done a test with a small neodymium magnet and it just slides right off which leads me to believe it isn't copper?

If I'm honest, it doesn't even look like copper - it's quite a matt brown until you shine a light on it. I'd say the 4th image is the most accurate in terms of how it generally looks. Bit like bronze?! I've absolutely no idea in all honesty so I am thinking it might be fake?

I've weighed it/measured it and all that seems about right so I was wondering if any of you experts can cast your eyes on it and help to provide a little more info? It'd be much appreciated!

Thank you,
John

I am no expert, but in Krause there is a bronze half penny listed as P-10b which is not on Numista.

Thanks so much for the reply! I'll do a little more digging with that info.

By the way, when I said experts, I basically just meant anyone that has more knowledge than me which I imagine is everyone on this forum! :)

Cheers!