'Abbasid Caliphate. temp. Al-Mansur. AH 136-158 / AD 754-775. AR Dirham (24.5mm, 2.52g, 5h). Tabaristan mint. Dated AH 147 / AD 764/5. Obverse: Three concentric annulets in outer margin with governor's name 'R-W-H' (for Rawh b. Hatim) between them. Reverse field: citing the caliphal heir al-Mahdi Muhammad. Lowick 2057; Malek 54B. Good Fine. Rare.