Most coins struck for use in Rome’s provinces were made of copper or one of its principal alloys. None are known in gold, yet some large and important issues were struck in silver or in billon (a composition of debased silver).
Because of their precious metal content, these silver and billon coins constitute a wholly different category than base metal issues.
The great majority of silver and billon coins issued in the Roman provinces belong to one of four categories: cistophori, Syro-Phoenician tetradrachms, the issues of Caesarea in Cappadocia or the coins of Alexandria in Egypt. Each category is distinctive and worthy of a separate discussion.
The cistophorus, a silver coin of three drachms, is thought to have been introduced sometime between circa 180 and 167 B.C. by the Pergamene King Eumenes II (who reigned from circa 197 to 159 B.C.). They were struck in very large quantities by this king and his successors, and large-scale production continued after authority in that kingdom passed to the Romans in 133 B.C.
The name “cistophorus” is derived from the obverse design of the Pergamene issues: a basket (the cista mystica) from which a snake emerges. The Romans retained that original design until about 48 B.C., with the last of these issues bearing the names of imperators, proconsuls, quaestors and praetors who were operating in Asia Minor.
From about 39 to 18 B.C. cistophorus production resumed on a large scale under the warlord Marc Antony (who died in 30 B.C.) and his nemesis Octavian, who continued to strike them after assuming the name Augustus and becoming Rome’s first emperor (27 B.C. to A.D. 14).
Nearly 60 years later, the Emperor Claudius (A.D. 41 to 54) struck another substantial issue. About a generation later, in circa A.D. 80, production once again began on a large scale, lasting for nearly 20 years.
Starting in A.D. 128 or 129, the Emperor Hadrian (A.D. 117 to 138) issued a very large number of cistophori using as his planchets old, worn pieces he withdrew from circulation. They were struck at numerous mints throughout Asia Minor, with the variety of reverse types being nothing less than extraordinary. Thereafter, cistophori were issued only sparingly with the last ones being struck by the Emperor Gordian III (A.D. 238 to 244).
This category of coinage is broad and varied in both the number of mints and the span of production, yet there is a great consistency in design, for the obverses feature the portrait of a member of the ruling family and most bear on their reverse a standing eagle. Some extraordinary bust styles and distinctive reverse types are found within the series, but those issues are rare and uncharacteristic.
At least 28 mints have been identified in this series, issued throughout the great swath of land spanning Mesopotamia in the north and Palestine in the south. Included are issues struck on the island of Cyprus, and we might add five mints in Cilicia, a region that neighbored Syria, for they also produced major issues of tetradrachms over a long period, notably during the reign of Hadrian.