Watch List notes:

ISLAMIC, 'Abbasid Caliphate. al-Hadi. Dirham (Silver, 23 mm, 2.89 g, 2 h), citing the caliph al-Hadi as 'al-Khalifa Musa' in Kufic, Kirman, AH 169 = AD 785/6. SICA III, 1173. Minor marks, otherwise, very fine.