'Abbasid Caliphate. temp. Al-Ma'mun. AH 199-218 / AD 813-833. AR Dirham (25.8mm, 2.95 g, 12h). Reform type with double margin on obverse. Madinat al-Salam mint. Dated AH 207 (AD 822/3). 'Reversed S' symbol at start of outer obverse margin. SICA 3, 1779-1780; Qatar 1895; Album 223.6. Lightly toned. EF.