Watch List notes:

ISLAMIC, 'Abbasid Caliphate. temp. Al-Mahdi, AH 158-169 / AD 775-785. Drachm (Silver, 23 mm, 2.11 g, 4 h), citing the governor of Tabaristan, Yahya ibn Mikhnaq (PYE 128-130 = AH 162-164 = AD 779-781), Tabaristan, PYE 130 = AH 165 = AD 781/2. Crowned and draped Sasanian-style bust to right; behind head, AFZUT GDH ('may his kingship increase' in Pahlawi); before head, 'Yahya' in Kufic; in outer margin, APD / NWKW ('excellent' and 'good' in Pahlawi) and floral ornaments. Rev. Sasanian fire altar set on three steps, flanked by two attendants standing facing; to left, date; to right, mint TPURSTAN ('Tabaristan' in Pahlawi). Album 60. SICA I, -. Walker, Arab-Sassanian, -. A very rare date for Yahya ibn Mikhnaq. Minor marks, otherwise, extremely fine.