RR-, 50 pennies 1938 nickel plated, G away from R in GROSZY (5% of population) beautiful and rare, additionally without mark

A very rare variety, where only 5% of the population is of this variety, in addition, a coin without a mint mark. The reasons for minting coins without a mint mark are described by R. Koter in PN2/98 in the article "Are there any 50 penny coins of 1938 without a mint mark?". - the variety was created due to mint damage to the stamp, hence the faint mint mark.