What made you draw the conclusion that you did - nevermind the date you attributed as that is obviously a typo? I'll give you hint - it is a mystery that has a reality in fantasy.
First time I've ever tried to classify one of these, so I took a dive into various websites and tried to interpret their info and what I was seeing on the coin.
I could be way off in almost everything. Heck, it might not even be a real coin.
As you pointed out, the date was a typo. 20th century is definitely out, if it is a real coin!
I thought 1572 style Reale from the configuration of the shield with the little center part in the middle of the quadrant.
Left of the shield looks like it could be oXM, which was explained as Mexico City mint. A little bit of elimination as the other mint possibilities for this style didn't seem to come close to matching what was there.
Right of the shield was explained as denomination and assayer. It was hard for me to figure the assayer, but considering the supposed date and style, "A" looked the most promising. I had to squint hard to make that look like an A, it really seems to be a YP to me, but that didn't make any sense according to the sites I was viewing.
The denomination was a wild guess, partially based on the size of about 0.75" across.
Anything you can do to educate me is appreciated.
I can't decipher your hint, but thanks anyway.
JayeLK