1/2 Real Legit?

And that's a very neat find!

I am not an expert on this type, and I wonder if anyone will be able to give a definitive answer with the dirt and/or corrosion in its current state (is that a glob of solder in the center of the back of the coin? Which can be from its being previously mounted. Or the lemon juice experiment?).

I have owned a number of 1/2 real pieces, some of them holed like this. The color can range from silvery to nearly black, so I see no issue with the color, especially given the environment.

Charles III 1/2 real coins are plentiful, so I would assume it is authentic.

To the Forum.
Very nice find!

From with I can see its a 1789. But better pics will help

I was thinking 1782. https://www.ebay.com/itm/1782-Mo-FF...047675.l2557
(scroll to bottom to see the 1/2 real)

But indeed, hard to tell from these photos.

@BillBurns, numista gives the diameter as 17.2 mm, so your diameter is fine. https://en.numista.com/catalogue/pieces18789.html