1 Grosz Trial Strike, inverted die

Poland's post-partition monetary reconstruction in the early 1920s involved extensive pre-production testing at the Warsaw Mint, and trial strikes with rotated or inverted dies are a documented byproduct of that calibration process. This piece is not a minting error in the conventional sense — it was never intended for circulation and was struck deliberately to test die alignment tolerances. Surviving examples almost never surface through normal auction channels, appearing instead through specialist Polish numismatic sales or old cabinet collections assembled before World War II disrupted so much of what the Warsaw Mint had retained.