Watch List notes:

ABBASID: al-Hadi, 785-786, AR dirham (2.95g), al-Yamama, AH170, A-217.1, without any governor, just bakh bakh below the reverse field, VF, RR. Al-Yamama was the first mint in Arabia to strike silver coins, located near the modern city of Riyadh, with its administrative capital at the town of Hajar. It operated AH165-170. The mint at al-Yamani was closed by the end of AH170, while a new mint at San'a in Yemen opened for silver coinage in 171, but to a much lower weight standard of about 1.25g.

Estimate: 1,500-1,800 USD