Australian Misstruck 1973 1 Cent

I can't see it being a mint error; nothing in the mint process could do that kind of damage post-striking.

I'm not entirely sure what would do that kind of damage post-mint either. It appears to be a failed attempt to split a coin in two, perhaps to try to make a two-headed or two-tailed coin.

Isn't there some euro coins that have edges like that? Maybe the ops' coin was struck on a wrong planchet? Most likely not though,most likely PMD.
John1

I have seen this sort of error on 2 cent coins. Sadly there is little info on the subject. My thoughts are it is some sort of collar die error. A railroad rim on both rims is something to be considered. Trying to explain these issues is a daunting task. I'm sure there are a lot of mint errors out there that get dismissed as "tooled" or manufactured but with machines anything can happen. There are a lot of errors that only exist in catalogues that most people have never seen in real life, and can be spectacular.
This coin would fall in to the Grey area where no-one is 100% sure either way. I would add I have seen this error(not so pronounced) on rotated pennies too.