1982 Twenty Pence Error Coin

Just looks like a corroded/discoloured 20p to me?
You can force them to do it by leaving them in a damp environment with bronze coins.

(There is an accelerated way of doing it with household items if you're really bored)



Alkali solutions brown them over really quickly.
Salt, white vinegar and aluminium foil in a bowl will 'copper tint' cupro-nickel coins pretty well if you get the balance right. I got bored and got the 'clean some coins' thing out of my system on 10p's one day during the recent slowdowns and noticed the reaction.
Not totally relevant but you never know when you'll find yourself that bored.

Not suggesting you've deliberately altered it, just pointing out that it can happen if kept under certain conditions.

The obverse/reverse photos are not really large or lit well enough to tell anything useful about it, and it doesn't look thin enough to be one of the '1p blank' strikes from the one large pic you uploaded.

They look kinda interesting when they've been through some hard times. Might have to bury some in the garden and come back to them in a few years.

Imagine if they'd been made 100 years earlier..


(I'm bored and waiting for a delivery)

Could you upload some better pics?
It's impossible to tell what you're trying to show without better lighting higher res photos.

Because I cannot see the pictures clearly and way too much lens flare I am guessing the top right 20p is the one in question. The only error that springs to mind is the coin is just the copper core and missed the nickel plating process. 84% copper 16% nickel. I have seen such a coin but for the life of me I cannot remember where.