Watch List notes:

ABBASID: al-Ma'mun, 810-833, AR dirham (4.08g), Nishapur (Naysabur), AH202, A-224, 'Ali b. Musa al-Rida, Imam of the Shi'ite faction, was named heir to the caliphate as part of a failed attempt to reconcile the Sunni and Shi'ite branches of Islam, superb strike, choice EF, RRRR. This is first known example of the Nishapur mint dated AH202 - only 203 has previously been reported, and still one of the rarest mints for this type (only Isbahan, al-Muhammadiya and Samarqand are relatively common).

Estimate: 2,500-3,000 USD