Roman Imperial Coins
Online Coins of the Roman Empire (OCRE), a joint project of the American Numismatic Society and the Institute for the Studyof the Ancient World at New York University, is a revolutionary new tool designed to help in the identification, cataloging, and research of the rich and varied coinage of the RomanEmpire. The project records every published type of Roman Imperial Coinage from Augustus in 31 BC, until the death of Zeno in AD 491. This is an easy to use digitalcorpus, with downloadable catalog entries, incorporating over 43,000 types of coins.
Roman Imperial Coins
As of April 2017, OCRE provides links to examples present in nearly 20 American and European databases (both archaeological and museum in context), including the ANS collection, the Münzkabinett of the StateMuseum of Berlin, and the British Museum, now totallingover 100,000 physical specimens. Between these collections, OCRE is now able to illustrate 50% of the imperial coin types that it contains. Moving forward, as more collections join theproject, it will eventually incorporate and display almost all recorded Roman Imperial coin types. Furthermore, it draws findspot information from another ANS-developed resource, Coin Hoards of the Roman Republic, enabling the mapping of the distribution of early Augustan types. Geographic data are also provided by the Portable Antiquities Scheme, Antike Fundmünzen Europa, OpenContext, and other partners. For more information on project partners, please see the contributors page.
The production of a chronological catalogue of Roman Imperial coinage was started in 1923 by Harold Mattingly, a numismatist at the British Museum, assisted by Edward Allen Sydenham. Their catalogue differed from its predecessor, produced by Henry Cohen in the 19th century. Cohen had classified the coins by emperor, and then alphabetically by the legend (text) on them. Mattingly broke down the classification further into which foundry, and in which series, each coin came from. Mattingly and Sydenham were joined by C. H. V. Sutherland in producing volumes IVb (1938) and IVc (1949), and by Percy H. Webb for volumes Va (1927) and Vb (1933). After 1930, the editorship of each of the final volumes was given to a specialist of the period. After Mattingly's death in 1964, Sutherland and R. A. G. Carson jointly took over editorship of the work.
The authority and personality of the Roman emperor and his government were mediated to the subject population in a variety of ways. Perhaps the most important was the complex of stories circulating probably even among relatively humble people, many of them about contact with the emperor or his representatives. Of course such contact itself, when it occurred, also mediated the authority and personality of the emperor and his government; the imperial cult, too, had an important role to play, as did the erection of figured monuments and imperial buildings and the distribution of imperial largesse. Within the empire as a whole, the plebs in Rome naturally had privileged access to the benefits of imperial rule and saw far more of the emperor and his works.
On the nature and importance within this context of the rôle of the imperial coinage widely differing views are expressed; at one extreme there is the view that the emperor himself paid particular attention to the choice of types for his coinage in order to draw attention to his virtues and his successes and that these types had a major impact on the population of the Roman Empire, at the other extreme the view that only a minor department of government was involved and that the pictorial types of the imperial coinage were little noticed and often misunderstood.
The provincial bronze coinage was produced by hundreds of cities, initially throughout the Empire but after c. AD 40 only in the East. The coins generally have a portrait of the emperor or a member of his family on the obverse, and a reverse which refers to the city in question, often one of its religious aspects.
Apart from Egypt, all these coinages came to an end in or before the 260s and 270s. The Egyptian coinage ceased under the emperor Diocletian (284-305), and thereafter the currency of the Roman empire was more uniform, produced at a network of imperial mints.
Except for a small number of silver issues, cities produced bronze coins, which circulated locally and provided the majority of small change in the Eastern half of the Roman Empire. During the Julio-Claudian period civic bronze coins were also made in the West, in Spain, Gaul, Italy, Sardinia, Sicily, Africa Proconsularis, and Mauretania, but after c. AD 40 civic coinage was made only in the eastern part of the empire.
A few coinages were issued in the name of a number of the koina (provincial or regional federations of cities) in the East. In the Roman period worship of the emperor lay at the heart of the function of koina, and their coins often depict a temple of the imperial cult. In other respects coins of provincial leagues resemble civic coins.
Examples are the coinage struck by the Kings of Bosporus which was centred on the straits between the Black Sea and the Sea of Azov. The Bosporan kingdom struck (increasingly debased) gold and bronze coins, Edessa silver and bronze.
In the majority of cases coins appear to have been struck at mints located in the cities named on the coinage, although some regional styles are apparent in the first century, raising the possibility of some sort of centralised or joint production.
Yellow = Type 1, green = Type 2, purple = Type 3, dark blue = Type 4, dark orange = Type 5, white with red outline = Type 6, white with black outline = Type 7. Numbers correspond to individual coins of each type as given in Table 1. Orange boxes = public collections, light blue boxes = private collections. Apart from the Glasgow group discussed herein, confirmed coins are Vienna Münzkabinett RÖ 32.227 and RÖ 32.228; Bologna, Museo Civico Archeologico MCABo Num 26424, Bibliothèque nationale de France K 2339 and number unknown; Münzkabinett der Stiftung Schloss Friedenstein Gotha, 1.Co14611 and 1.Co14612; and Brukenthal National Museum, Sibiu.
Nevertheless, arguments against the fakery hypothesis can also be raised. The coins of the Sponsian assemblage are highly atypical of early cast forgeries in that they used newly engraved designs as hubs rather than real coins. The standard of engraving is not very accomplished and is not aligned with the classical aesthetics that dominated the early collecting market. There was little public interest in third century Roman history in the eighteenth century; all the early fakery that we know of featured Greek or Roman figures of greater renown from a more classical period . It also seems odd that Sponsian was given such an involved context of other fake designs, that his coins are numerically in a minority among the known wider assemblage (the most common design among surviving pieces being the Type 2 Plautius coins), that they are the least impressive of the various designs, and that no special care was taken either in the engraving (especially the obverse legend down one side of the head only) or manufacture (the hub slip on GLAHM:40333, for instance, seems careless). If early price catalogues from 1823 onward  are taken as a guide, the Sponsian coins were not especially valued by collectors in comparison to those of well-known emperors.
Although the four questionable coins have always been described as gold, we wanted to determine the level of purity in comparison to the genuine Roman aurei. We also wanted to test the suggestion that they may have had a large base metal content that could have produced a reddish oxidation product of the surface, as has previously been suggested . We analysed the metal composition of all six coins by SEM-EDX. For consistency this was done by a standard procedure on worn upper surfaces of the obverse bust, avoiding superficial deposits where possible. A series of spot tests was taken which may not, however, be representative of the bulk composition if there are significant heterogeneities, as was found to be the case for the questionable coins. Therefore, a second series of analyses was conducted in various other areas widely distributed across the reverse side of these four coins. Results are plotted in Fig 4 and summarized in Table 3.
Additional evidence of the manufacturing process begins with the fact that the designs have evidently been copied from genuine coins but are not of normal style, quality, or level of detail. The legends are frequently poorly spelled, ungrammatical or even meaningless in one instance, and in some places have been omitted, apparently through lack of space, squeezed in, or filled out with arbitrary (see Table 1). Some of the design elements have been reproduced in mirror image as would happen if an engraver began the work in negative relief and did not take particular care to flip the image. Another characteristic feature of the coins is that the blank fields often feature one or two sets of linear ridges (for example, see Fig 5B and 5D and S.1.6.3 in S1 File). The precise pattern of these ridges is common to multiple coins, including previously photographed specimens in other collections , hence they must have been inherited from a common hub. These lines are truncated by the engraving and so seem to have been present on the sheet (presumably metal) onto which the designs were first engraved. As far as we can determine, having examined all available photographs, only one obverse and reverse hub was used for each type of coin.
UV photography revealed several areas of white fluorescence on the various coins. Some of these correspond to places where we observe reddish deposits in LM, suggesting the presence of a fluorescent mineral such as calcite (Fig 9). Apart from very bright, white fluorescence visible in some places, most of the coins show a faint, orange glow, a colour that might be distorted away from whiter, paler hues due to the thinness of the glowing layer. This indicates the widespread presence of fluorescent minerals in small patches across the coin surfaces. The amorphous white substance on the Sponsian coin (GLAHM:40333) also fluoresces in white (Supporting Information S.2.6) and was confirmed to be wax by r-FTIR (S.6.6 in S6 File). We speculate that at some stage a wax impression was made of this coin, possibly the cast viewed by Cohen in Paris . A very small ovoid patch on the reverse of one of the Philip coins (GLAHM:29821) below the spearhead fluoresced brightly in orange (see Fig 9D). Analysis by r-FTIR (see S.6.5.2 in S6 File) confirmed this as shellac resin, a substance that is known to fluoresce strongly (e.g., ) and is very common in conservation environments: it is interpreted as adventitious. 041b061a72