Inevitably, there are coins of almost every country or period that do not easily fit into exact classifications. Sometimes weights, denominations or planchet sizes are mutant to the regular issues. At other times, design or motif may be atypical. Although anathema to the compulsive classificationist, these deviants do exert a special charm and challenge to most numismatists.

The issues of Roman Egypt are rather rich in odd and unusual coins. We have already encountered in a previous chapter the rare billon didrachms of Claudius. This denomination lay dormant till the joint reigns of Aurelian and Vaballathus, at which time some experimentation took place. The author has the single known specimen of a potin didrachm of these emperors. The coin resembles the contemporary tetradrachms, with the busts of the rulers on either side, but is only 19 millimeters in diameter, weighs only 4.27 grammes, and has the obverse and reverse dies rotated at 80 degrees to each other. The edges appear to have been "rolled" at the mint, before striking. This appears to have been something of a pattern issue that did not meet with favor. The obverse die was salvaged, however, and the author has a tetradrachm of Aurelian of normal characteristics, with full size reverse die, but with an obverse struck from the same reduced size die of the didrachm.

Domitius Domitianus, during his coinage reform, revived the denomination for the last time. In addition to octadrachms (equated with antoniniani) and tetradrachms, this emperor struck potin didrachms, all bearing reverse types of Nike.

Returning to the issues of Aurelian and Vaballathus, we find an illustration of the reverse of one of their experimental coins at the top of Plate XLII. Bronze drachmas and half-drachmas appear to have been struck, although there is some doubt as to the actual denominations intended, as well as whether certain variants in size represent even- a third value. All bronzes, however, have the same motifs. On the obverses are busts vis-a-vis of the two rulers. The present illustration, of a half-drachma, depicts the reverse type. We see a laurel wreath enclosing the regnal dates of both emperors. All bronze coins of the joint reigns are quite rare.

The second coin illustrated at the top of Plate XLII represents another deviation from normal coinage practices. The bust of the empress Julia Mamaea is shown as it appears on a tetradrachm of Severus Alexander. It will be immediately noted that the style of the coin is more Roman than Alexandrian. The lettering is finer, the coin edge is more rounded, and the art work more conventionalized than on the regular tetradrachms. Moreover, the dies were rotated to a 180 degree position. This coin is one of a series issued for two or three years during Alexander's reign (along with the more "normal" style) which seem to reflect the influence of officials or workmen imported from the mint of Rome.

The next two coins encountered on the plate are common tetradrachms of regular style. Both, however, depict types that are difficult to place in the categories described in previous chapters. The tetradrachm of Pius shows the "wolf and twins" motif, referring to the mythological founding of Rome. This was borrowed directly from the Roman coinage. The coin of Marcus Aurelius shows two right hands clasped, in a gesture of "homonoia." This too was adopted from the regular coinage of Rome. The first motif is found from the reign of Pius and Aurelius sporadically through that of Aurelian while the second occurs on tetradrachms of Hadrian, Pius and Aurelius.

We next encounter a drachma of Pius depicting Hermes seated on a rock, holding a purse and a caduceus. This is an unpublished type. The only other known coin showing Hermes seated was issued by Caracalla. The latter piece, a drachma, varies considerably from the coin illustrated here.

Plate XLII is completed by a controversial tetradrachm of Hadrian. This extremely rare coin has a reverse type that has long been considered as portraying the head of the deified Trajan. However, the lack of the customary inscription for such types would contraindicate this, as would the use of the lion skin headdress, rather than radiate crown or laurel wreath. All Alexandrian coins honoring deceased predecessors seem to have included names and titles. It seems more probable that we have depicted here the head of Herakles-Harpokrates. It is quite significant that the coin's date L H (year eight) falls in the period during which many fresh Greco-Egyptian types were issued.

The first four illustrations of Plate XLIII are of unusual treatments of Sarapis. The exact meanings of the types are rather obscure. All are quite rare, and do not seem to have met with any degree of favor.

A drachma of Caracalla depicts the bust of Sarapis receiving a salute from the emperor, who is standing in a quadriga. It is possible that this type represents Caracalla's acceptance of Sarapis as an imperial protector and patron of victory.

The following illustration is of a drachma reverse of Antoninus Pius. This unpublished coin shows Sarapis seated on a sacred ram of Ammon. A much different type identified as "Sarapis Ammon" appears on coins of Hadrian, and our present reverse may be a variant expression of the same syncretism. The only other known instance of the present type occurs on an extremely rare issue of Trajan. For reasons unknown the edge of the author's coin was serrated in antiquity.

Immediately below the two reverses described above, will be found an illustration of a drachma of Trajan which shows Sarapis seated between the standing figures of Harpokrates and Hermanubis. This is an extremely rare issue which seems to have occurred only under Trajan. Once again, the objective seems to have been connected with efforts toward syncretism.

The remaining Sarapis type depicts his bust above a human foot and lower leg. This motif first occurs in Pius's last year, and is found on rare coins of Marcus Aurelius and Commodus. The exact meaning is not clear. It is interesting to note that the human foot and lower leg, as an ancient Egyptian hieroglyph, has the meaning of "place" or "position," as well as the alphabetical value of the letter "B". There may or may not be a symbolic connection with the coin type.

The final two illustrations of Plate XLIII, as well as all of Plate XLIV, are devoted to reverses of "nome" coins. The nomes were administrative areas of Egypt. Existing since earliest dynastic times, they were identified with the petty kingdoms and similar political units which had existed before the unification of Egypt by the first dynasty pharaohs. The nome system survived the many dynastic changes, foreign invasions and the Ptolemaic rule, and was continued with modifications by the Romans.

All nome coins were in bronze, and were struck at the Alexandrian mint. All were identified by Greek legends containing the names of the specific nomes, or their abbreviations. The various motifs were intended to represent the local deities or sacred animals. The mint officials, however, apparently had little knowledge of many of the local cults. As a result, few of the coins shed much light on contemporary religion, and some must have appeared rather ridiculous or offensive to the actual residents of several of the nomes. It should be noted that these pieces were issued for general use, and were not intended to circulate exclusively in the designated nome.

The first group of these coins were issued by Domitian, in the half-drachma denomination. Trajan, Hadrian and Pius continued the series, but in drachma, obol and dichalkon values. A thorough study of the nome issues would require a separate article in itself. The nine types presented here were chosen for their general contribution to a survey of Alexandrian coinage as a whole, or for their special interest, and are not intended to be definitive.

The two nome types which conclude Plate XLIII show unusual representations of Isis. The first, of the Nesytes nome, is unpublished. A drachma of Trajan, it depicts Isis standing with head turned, regarding a small figure of an Apis bull, which she holds in her right hand. The second, a drachma of Pius, is of the Memphite nome. In this rare type, Isis stands before a small Apis bull. She wears a vulture headdress, and holds a staff and uraeus in either hand.

The top three illustrations of Plate XLIV are of obols of Hadrian. We first encounter a coin of the Memphite nome which depicts Isis standing, holding a small figure of Harpokrates on her outstretched hand, while her turned head regards an uraeus, which rests on her other hand. The next coin, of the Hermopolite nome, shows the bust of Thoth, with a diminutive Ibis before it. Thoth, ancient Egyptian god of wisdom and knowledge, is not encountered on the "regular" coinage. The remaining obol, of the Arsinoite nome, depicts the head of a pharaoh, wearing royal headdress, with uraeus and beard.

A bronze drachma of Aurelius Caesar, representing the Heliopolite nome, is next. Helios is shown radiate, holding a staff in his right hand, while he regards the Mnevis bull held in his outstretched left hand. This type is extremely rare.

The Leontopolite nome is represented by a drachma of Pius. Horus is depicted standing, with a scepter in his right hand, while his left bears a small figure of a lion.

Plate XLIV is completed by two unpublished drachmas of Trajan. Issued for the Ombite nome, the first of these shows a youthful male god, resting his left hand on a long staff, while in his right he holds a crocodile. He is crowned with disk and horns. The second coin appears to be the only known nome coin to depict two deities and to represent (apparently) two nomes. The nude male figure, extending a bust in his hand, is a standard type for the Arsinoite nome. The standing figure of Sarapis, sacrificing over an altar, seems to represent the Alexandrian nome. Legible parts of the inscription seem to confirm the two words "nome" and "Arsinoite." The type may have been intended to represent dependence of the nome upon the officialdom of Alexandria, or perhaps to represent a "homonoia" theme.

This article has done little more than "scratch the surface" of the fascinating subject of the Alexandrian coinage. The numismatist who wishes to specialize in the series will find rich rewards. In addition to the vast amount of knowledge that can be gained, there remains always the possibility of discovering new types or varieties. So varied was the coinage of Roman Egypt that a "complete" catalog will probably never be written.