Watch List notes:

Arab-Khwarizm, al-Fadl b. Sahl, ½-Drachm, no mint or date, obv. bust right, rev. horseman right, al-fadl in left field, 1.80g (Frye 3-4). Fine, very rare. al-Fadl b. Sahl (d.202h), also known as Dhu'l-Riyasatayn, was the vizier of the caliph al-Ma'mun.

Estimate: £300-400