@MRV, clearer pics (cropping would be super-cool) would help, but I think that I see enough to tentatively attribute this coin to 15th Century Poland. It looks to me like the side with the crown has an inscription something like REGIS POLONIE while the side with the eagle at least starts with MONETA. Maybe from Casimir Jagiellon? I can chase it further if you can add better pics to this thread. Right now, this is the best that I can do with magnifying and enhancing your pics:
"If you climb a good tree, you get a push." -----Ghanaian proverb
"The danger we all now face is distinguishing between what is authentic and what is performed." -----King Adz
I am leaning toward a 1/2 grosz of Jan Olbracht (1492-1501), the next Polish ruler after the one suggested by @spence. On reverse, the legend starting at 6:00 below the eagle would be I * AUBERTI which I think fits a bit more closely to what I see in the new photo than KASIMIRI.