'Abbasid caliphs
al-Hâdî Mûsâ, 169-170 H./785-786 AD. Dirham 170 H., al-Muhammadîya, with the name of the caliph and the marks bâ-râ above and sâd below the rev. field. Lowick/Savage - and in none of the collection catalogues. 2.86 g.; Known for 169 H., but extremely rare for this year About extremely fine
Acqu. Jean Elsen, Brussels, list 224, March 2003, no. 535.