Watch List notes:

ISLAMIC COINS, ABBASID, al-Ma'mun, Gold Dinar, no mint (Misr), 199h, citing dhu'l al-riyasatayn al-Fadl, vizier, and (a)l-Muttalib [sic] Governor of Egypt, 4.22g (A 222.5; Bern 86). "X" and minor abrasion to reverse, otherwise extremely fine and rare.

Estimate: £300-350