Emperor standing, holding globe and a long cross / Large m; cross above, uncertain letters around, KAST in exergue. 22mm, 3.46 grams. Carthage mint. Walker -.
The type with a full-length figure on the obverse is not listed in Walker.
These coins are among the earliest coins of the first Islamic Caliphate. Before the more familiar anepigraphic types were issued by the Ummayad, the arab conquerors used a slightly modified Byzantine coinage in the conquered Byzantine lands.