To Peter: I saw indeed once such a 4 on a coin from Harar dated 1304, usually they used there the Persian 4, but there exists also at least one piece with a Western Arabic 4. Anyway I cannot see any trace of a 6, as all bars, which are not a 1, would belong to the 4.
To Bernard: Many thanks again! Two more of these will follow, then I will continue with silver coins, before I will come back once to these coppers.
ca 20 mm
4.0 mm thickness
8.68 g