Poland, Second Republic, 20 groszy 1923, counterfeit from the era, very rare
denominations rarer than the zloty were rarely in circulation, and the 20-groszy is practically unheard of on the collector's market
no listing on ONEBID.pl
gray metal (czynk? lead?) magnetic
on photo 3 comparison of thickness of counterfeit and original (counterfeit on the left), on photos 4 and 5 counterfeit on the left
weight 2.79 grams (the original nickel 3 grams), diameter 20 mm consistent with the original