A very rare denomination of the "three brothers" one-coin mint, especially in the presented variety, with the number 5 reversed in the date.
In the specialized catalog "Common Minting of the Three Brothers 1651-1662", by Marcin Grandowski, the variety with the degree of rarity R7-, which means 9-10 pieces known to the author.
Piece slightly deficient, but correct.
High rarity.
