Poland's coffers were not overflowing with riches after the second world war. In the post-war years, they minted coins with similar patterns in bronze as well as aluminum. The latter is a very light metal - collectors rarely take kindly to these coins, which can almost feel like they are made of plastic covered in metallic paint.
These aluminum coins all have an eagle on one side. Except for the 1 zloty, they all have the denomination above a sprig on the other side - the zloty has its face value pictured within a wreath.
Circulated coins are worth very little. A keen collector might pick up a circulated but well preserved coin with good eye-appeal for a couple US dollars.
Absolutely, fully uncirculated coins are not as common as circulated examples, and these have some collector value.
The approximate catalog values below are for fully uncirculated coins only:
1 Grosz: $3 US dollars approximate catalog value for uncirculated coins
2 Grosze: $4
5 Groszy: $5
10 and 20 Groszy: $9 and up
50 Groszy: $18 and up
1 Zloty: $20 and up
These values apply to problem free coins that are not bent, holed, stained, scratched or anything like that. Be sure to read the 'Important Terminology' page on the top left to properly interpret these catalog values.