XXI and Other Letters

....or Things Found on Roman Reverses of the Late Third Century AD

Beginning in the middle of The third century AD, a characteristic of Roman coins was the use of abbreviations on the reverse to indicate the mint city ('mintmark') or other pieces of information of interest to collectors. Some are rather obvious in meaning; others have been objects of discussion among numismatists for over a century. This week out Featured Coins were selected to show interesting uses of one or more of these abbreviations. While the ones we present demonstrate the standard uses they also include some varieties best described as 'odd'. This coverage is not intended to be comprehensive. To cover this subject fully would require showing thousands of coins. These are just a few examples of what a collector needs to study when learning the language of coins.

This follis of Galerius Caesar (c.301 AD - I know I said Third century but close will have to count.) bears the figure of Genius holding a cornucopia and pouring a libation from a patera. Under the figure ('in exergue') is 'ALE' placing the mint city at Alexandria, Egypt. In the field to the right of Genius is the letter 'A'. Note that all letter A's on this coin have a slightly open top and could be mistaken for H's. In this case the 'A' is the Greek numeral 'one' and represents the first workshop (officina) of the five then operating at this mint. This same coin exists with B, G, D and E in place of the A. We will see other methods of workshop designation later. The item of controversy on this coin is the XX I split across the field. Beginning with the currency reform of Aurelian (c.270 AD) we see this numeral on many silvered antoniniani. Only very rarely was the mark used after the reform of Diocletian (c.294 AD). Some scholars considered this to be a mark of denomination to be read: "20 of something is worth one of something else." Others read it: "This coin contains 20 parts copper and one part silver." Since the XXI is commonly found on the smaller and earlier antoniniani, the use on this large, post-reform follis adds greatly to the credulity of the metal ratio reading. RIC (Vol. VI) places great emphasis on the association of this marking on the follis with the Edict of Maximum Prices setting a value in gold for the coins. Both coins were struck from the same alloy (about 4.7% silver). I tend to accept the copper/silver ratio reading and cannot believe that it would mean something different on the follis after years of use on the antoninianus. .

An Antioch mint antoninianus of Numerian Caesar (282 AD) bears no city mark. It does, however, use the XXI ratio mark and a particularly interesting Greek numeral for the officina. The Antioch mint was organized into nine workshops using standard Greek numerals for 1 through 8 (A-H). The ninth officina used 'ED' or 5+4 in place of Q, the proper numeral for 9. In addition to being the numeral 9, Q was the first letter in thanatos (death). As such it was considered an unlucky symbol to be avoided much as many people today avoid the number 13. This coin also shows the unusual triple GGG abbreviation but that is another story we have told previously.

At first glance this Ticinum mint (by style) Probus would seem to have the officina numeral in the field and the city initial before XXI. That interpretation turns out to be 100% incorrect! Comparing other coins from this series we find 'T' does not stand for 'Ticinum' but is the workshop initial (T=tertius=3rd). The series for the 6 workshops at this western mint is P,S,T,Q,V and VI. Since the words for 'fifth' and 'sixth' would start with a letter previously used ('Q' and 'S') Roman numerals were used in their places. The 'V' in the field turns out to be the strangest of all categories of reverse letters: the secret code. If you line up a series of six coins, one from each officina, the field letters spell 'EQVITI'. A more rare series spells 'AEQVIT'. Both spellings were used in the third century for the word 'cavalry'. Our example, being from the third workshop, bears the third letter of the code word. Was this secret mark a measure to foil counterfeiters? Is there a better answer to the question: WHY? A separate page expands this site's coverage of the EQVITI series. As we shall see in out next paragraph, it gets even stranger than this.

Issued before the currency reform of c.294 AD, this Siscia mint antoninianus of Maximianus I bears, in exergue, the XXI followed by an even stranger code sequence. The mint was divided into only three workshops using Greek numerals A, B and (here) G. To the right of G is LI. Conveniently, dots separate the sections of the mark. To make sense of this marking, one must find an example from workshops A and B. These coins read XXIAHP and XXIBKOY. Combining the fragments in officina order gives HPKOYLI or the Greek letter spelling of the Roman name Hercules. This is our code word. A matching series by Diocletian used I+O+BI or the Greek letter spelling of Jupiter (IOVI not Zeus!). I told you it was strange! :) I have added a separate page on the coded coins It is interesting that mints located in the Greek speaking part of the Empire were likely to use Latin based codes wile those from the Latin regions could use Greek. Here the same mintmark combines the Roman numerals XXI and the Greek letters for the name of the god.

The coins previously shown on this page are interesting but not particularly uncommon and are fully cataloged in the standard reference RIC. The coin shown to illustrate this next point is unlisted and a bit rare. The mark XXI, the Roman numeral for 21 or 20:1, was translated into Greek the numerals KA (=20+1) at some eastern mints. This antoninianus of Probus was produced at Serdica by the fourth (D follows KA) officina. What is unusual about this coin is that while most coins of Serdica bore no city mark, this shows MS (moneta Serdicae) in the field. This is similar to the common Cyzicus use of MC or CM. This particular type showing Victory and the Emperor is not listed in RIC. A few other reverses, however, do show this style mintmark. Recent hoards found in the area of the Eastern Empire are making the discovery of new types a common occurrence.

Mintmarks continued to be used for the remainder of the Roman period. During the fourth century, the use of a city abbreviation became much more common than it had been during the period covered by this page. The content and format of these marks varied from mint to mint and year to year. Our little survey here has barely scratched the surface of an interesting area of numismatics.

Postscript: While researching this page in 1998, I posted a 'want ad' on an internet numismatic discussion list in an attempt to see how difficult it would be to find specimens of the coins discussed on this page. I was told by more than one person that the EQVITI and HPKOYLI coins were extremely rare and that they had seen 'only one' in years of looking. Ten minutes later I found an EQVITI of Probus offered on a coin site. I went to my favorite resource (old auction catalogs) and found sixty 'coded' types (Probus, Maximianus and Diocletian) in the first fifty catalogs I checked. These catalogs were a mix of auctions and buy/bid sales offering 500 to 1000 lots. Two Harlan Berk buy/bid catalogs listed 12 such coins each! I stand by my statement: These coins are not rare. The problem would seem that dealers rarely see this matter as worthy of notice. Of the sixty listings found, only one (CGF, a French dealer) identified the coin (a Maximianus KOY) as part of the series. Learn two things from this: If you want to collect something, keep trying. Don't let someone talk you out of your interest. Second: Many coins have some point of interest beyond the obvious. The more you study, the more fun you will get out of collecting. After studying these things for thirty years you will have barely scratched the surface of what there is to learn.

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(c) 1998 Doug Smith