Pre-reform issues, Tabaristan ('Abbasid governors). Umar b. al-'Ala. AH 155-165 / AD 771-780. AR Hemidrachm (23.7mm, 1.73 g, 2h). TPWLSTAN (Tabaristan) mint. Dated PYE 122 = AH 157 (AD 773/4). 'Umar in Arabic before bust / Star to left, crescent to right of altar flames. Malek 66.1-5; Album 57. Some reverse luster. EF.