Watch List notes:

ISLAMIC COINS. ABBASID (THIRD PERIOD). al-Mustazir billah, Gold Dinar, Madinat al-Salam 493h, 1.96g (Jafar, Y, Seljuq Period in Baghdad, 493; A B266). Extremely fine and thus extremely rare.
This is a rare variety of this mint and date, struck only in the names of the Caliph and his heir Abu-Mansur, when dynastic struggles could not resolve the question of who was the Caliph's Saljuq overlord.

Estimate: £2500-3000