I agree... without litterature reference, it's quite impossible to identify a coin in such condition. I obtained two coins of this mint among a small lot of coppers, from a person who bought them in Yazd, all were unidentified and I took them by courtesy because I thought they were nothing else than "pieces of metal" (

).
The unusual position of the legible date allowed me to find it in "Coins of the Shah of Iran" and the few parts of the legends present then appeared to perfectly fit with the legend.
There is today a controversy about what was previously read as the mintname "Ra'nash", which could be better the ruler's name : "Abbas" (Shah Abbas I).