Al-Mustansir, under whose reign this quarter dinar was issued, was the eighth Caliph of the Fatimid dynasty that ruled over North Africa, Sicily, Egypt and Syria. His period of Caliphate lasted for 60 years, the longest of all the caliphs, either in Egypt or elsewhere in Islamic states.
In common with the other Fatimid Caliphs; he issued mainly gold dinars and quarter dinars. Silver coins, on the other hand, were rarely struck under Fatimid rule.
This related to the circumstances before the Islamic conquest: The Persian Sassanids had struck only silver coins, due to the silver deposits in their territories, while Byzantium had used a gold currency. This situation persisted after the Islamization. Thus in Iran and Iraq silver coins prevailed, whereas in Syria, Egypt, Ifriqiya and Sicily people paid mainly with gold. Only in Baghdad, where money from all parts of the empire accrued, both coin metals were common.
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