The Byzantine Empire issued the gold solidus, or nomisma, used primarily for large transactions such as tax payments, and several denominations of copper coins, the money of daily business transactions. Mints in Antioch and Alexandria supplied the majority of the coinage circulated in the southern provinces. The newly established Arab government inherited an efficient monetary system and made few changes during its first decades. The caliph ‘Abd al-Malik (r. 685–705) introduced several issues of distinctively Islamic coinage. Coins issued in Egypt are less varied than those of Syria, though they do follow similar patterns. Under the governor ‘Abd al-Aziz, ‘Abd al-Malik’s brother, a series of distinctive Islamic coins was issued. Archaeological finds suggest that Syria and Egypt formed separate economic zones.This coin with overtly religious symbolism on the reverse (an alpha and omega flanking a cross) may be an example of an unofficial ecclesiastical issue by the Miaphysite patriarch of Alexandria Benjamin (r. 626–65), who was expelled by Heraclius (r. 610–41) and the orthodox bishop Cyrus at the time of the Arab invasions.