Silver hemidrachm, Governor 'Umar, 122 PYE/773 CE, Abbasid Caliph al-Mansur, Tabaristan

Sassanian-style bust right, wearing winged crown surmounted by star and crescent, crescents with stars, Pehlavi words GDE 'pzwty (combined to mean roughly "may kingship increase", left of bust), 'Umar (to the right of bust in Arabic), NYKW ("Good" lower left) and APD ("Excellent" in lower right) // Fire altar with two attendants standing facing, crescents on their heads, Mint name in Pehlavi (tpwlst'n for "Tabaristan") to the right, date written out in Pehlavi to the left. 23mm, 1.83 grams. Album #56; Walker, Arab-Sasanian, p. 138, 271; A 56; Numista #78512.

Umar bin al-'Ala was originally a butcher from Reyy, who became an accomplished soldier. He took part in the suppression of Sunbadh's revolt in 137AH and was sent to Tabaristan by the Abbasid caliph al-Mansur in 141AH to take part in its conquest with Khazim ibn Khuzayma, after this conquest he appears to have remained in Tabaristan.

Coins are dated in the post-Yazdigerd era (PYE) calendar, PYE = AH - 34.