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One ACE Teacher's Guide for Teachers

by Kate Gilbert

The moment when you first open your ACE packet and the coins spill out is both exhilarating and a little scary. Who amongst us has not thought for at least a second at that point, “What on earth have I gotten myself into?” Unless you already happen to be a numismatist, what you’ve gotten yourself into is definitely unexplored territory. And yes, occasionally in the coming days the sweat will break out on your brow and/or your upper lip and maybe you’ll even wish you’d stayed at home to watch the soaps instead of coming to work. But for the most part, the opportunity to start from scratch and learn alongside your students is a great gift – for you, certainly, but maybe even more so for them.


After all, that Roman coin you’re sweating over is a golden (well, bronze) opportunity to model the vital skill of problem-solving for your students. Even if you never reach a full identification, you and your students together can explore various avenues that will get you to at least a partial one. You can gather hard data such as weight and diameter; research the basic elements of Roman coin design and the most common types of images; eliminate many possibilities through trial and error; compile what you’ve learned into a report to share with the ACE experts; and possibly use their input to refine your conclusions even further. As great as it feels when you can nail down a conclusive identification, it’s even more satisfying just to share the adventure – even when you occasionally find yourselves down a blind alley together.

The suggestions that follow are based on my experiences during my first three years of participation in ACE with my high school students. You will, of course, develop your own methods, but this approach has worked well for me.

1). Work on a sample coin yourself – Before you introduce the coins to the students, pull out a coin for yourself and work on identifying it. By far the easiest way to master the basic info about coin design and inscriptions and the ACE resources is to work through it all with an actual coin in hand.

2). Don’t be afraid to pre-sort the coins, if you have more than you need – If you’re going to be pressed for time, or if you’re working with students who – because of age or temperament – have very short attention spans, I myself think it’s okay to pull out the coins that are easiest to read and start with them. I put the whole ACE packet into the pot the first year, thinking it would be cheating to pre-sort them at all. The result was that while several of my students got difficult coins, several coins languished unchosen that would have been easier for us to work with. Of course it’s important to prepare students ahead of time for the possibility that some coins might seem more approachable, unusual, or exciting to them than others and for the fact that the draw is both random and final -- no swapping or second tries. Still, you do want a satisfying experience all around, and if you have any surplus to play with you might as well do a little culling before you start. Despite your best efforts, some students may look at their friends' coins at the outset and decide that theirs aren't as "good." Usually, though, by the end of the project you will have identified something unique about each coin that makes the owner pleased to have it. One coin will have the clearest emperor's image, another the best-preserved diadem, and another the most legible inscription. One will be the oldest. One might been minted in the western half of the Empire while the rest were minted in the east. One might have an eagle and another a phoenix. And so on. In other words, some coins will be easier to identify than others, which is the point of pre-sorting, but they're all going to be in some sense "good" ones.

3). When you start identifying, concentrate on likely possibilities – Nearly all ACE coins fall into a narrow range of possible identities. More than likely, you will have a small copper-alloy coin from sometime in the fourth century C.E. It will have a head on one side, usually an emperor or a member of his family, and some sort of design on the other. The most likely “heads” are Constantine the Great and his co-emperor Licinius; Constantine’s sons; Licinius II; and a few other late emperors such as Valens, Valentinian I and II, and Arcadius. You might also get a woman in a helmet, representing either Rome or Constantinople; a veiled man, representing the dead Constantine on a posthumous coin; or possibly one of a handful of earlier emperors such as Probus. Several guides to the most common kinds of reverses and obverses are included on the ACE CD and at the website. If you focus on the likeliest possibilities, you can avoid getting frustrated or sidetracked by all the many other possibilities offered by five centuries of Roman imperial coinage.

4). Start with the measurements – Every coin, no matter how inscrutable, can be measured, and it’s both helpful to the ACE experts and satisfying to the students to have solid quantitative information. Students should measure the diameter of their coins at the widest point, in millimeters. If at all possible, they should also use a digital scale to get the weight to the nearest tenth of a gram.

5). Work on the obverse image first – In my experience, the best questions to ask your students immediately after the measuring stage have to do with the obverse, or heads side. These are:

  • “Which is the heads side?”

  • “Which way is the head facing?”

  • “What’s the figure wearing on its head?”

  • “Is the figure shown from the neck up, or can you also see the shoulders?”

  • “If you can see the shoulders, what’s on them?”

In order to answer the third and fifth questions, students will need to be familiar with the basics of what the figures on the obverses wear. Although it’s great if the kids actually learn the terminology, the most important thing is for them to know that there are several types of headgear and styles of dress, and to be able to match the type on their coin with the appropriate picture or description. The ACE CD includes a file called "A Short Guide to Obverse Images" that describes and illustrates the most common types.

If the coin is hard to read, it may not be all that easy to see what the figure is wearing. Certain telltale features often survive, though, even when the rest are obscured or worn away. Here are some clues to look for on the head:

  • Dots or bumps, lined up in a headband arrangement and found at the flyaway ends of ties behind the figure’s head. These tell you that the figure is wearing a pearl diadem.

  • A prominent bump over the figure’s forehead. This is the central jewel in a diadem.

  • Spikes radiating from the figure’s head, the signature of a radiate crown. A well-defined radiate crown may also show a bow or simple ties in the back.

  • The sharp lines of a helmet’s crest or visor. Sometimes the helmet will also have a diadem or radiate crown on top.

  • Two smooth or dashed lines in a headband arrangement, possibly with a bow or simple ties behind. This might be the remains of a laurel crown. A well-defined example may still show traces of the leaves.

  • Rosettes in a headband arrangement – another type of diadem.

Here are some things to look for when identifying the clothing on a bust:

  • Anything that looks like a fold or crease of cloth. This indicates that the figure is draped in a cloak or mantle. Even if you’ve lost most of the drapery, even a fold or two will be enough to tell you that there’s cloth involved in the design.

  • A bump or circle in the shoulder area. This is probably the remains of the brooch that pinned the cloak.

  • A square neckline and/or something that looks like short sleeves (with or without a cloak on top). This indicates that the figure is cuirassed.

! Note: It’s very tempting to linger over the ruler’s physical characteristics and try to make an identification based on portraiture. This, however, is usually a dead end. While numismatists sometimes have seen enough coins to be able to recognize a specific person from something like his hairdo or the shape of his nose, in general the images on coins of this era are too generic to offer that kind of help to beginners. It’s fun to take note of the hairstyle, build, and facial features, but these are mostly a sideshow.

5) Work on the obverse inscription next – Although the easiest place to start is the image, the really important part of the obverse is the inscription. This will help you move from a more or less generic picture to a specific identification of the emperor who issued the coin. Unfortunately, this is also probably the most daunting part of the coin for beginners to work on, especially those of us with middle-aged eyes. Here are some tips that may help:

  • On the common ACE coins, the inscription goes in a curve around the rim of the coin from left to right, starting at around 7 or 8 o’clock and ending at around 4 or 5 o’clock.

  • Sometimes the top of the head breaks the inscription; sometimes the inscription goes over the top of the head, unbroken.

  • There's usually little or no space between the words; everything tends to be run together.

  • The inscriptions are often heavily abbreviated.

  • The letter U reads as a V: CONSTANTINVS.

  • The crucial part of the inscription is the part where the main name is. At the end, and usually at the beginning too, you’ll find titles and attributes which, though they offer clues, are less helpful. Sometimes there are also abbreviated forenames before the main name.

  • Many ACE coins have inscriptions that end with PFAVG (“pius felixque augustus”). If you can identify this, you can back up from there to find where the main name ends.

  • Another possibility for the end is NOBC (“noblissimus caesar”). This tells you that the coin has been issued in the name of a caesar, or emperor-to-be, rather than a ruling emperor. If you happen to get this at the end of your inscription, you can narrow the field considerably by looking just at the handful of caesars within your time frame. If the caesar has the same name as his father (as, for example, Constantine II), the inscription will also include IVN (“iunior”): [somebody] IVNNOBC. Working backwards, the main name will end just before NOB (or, if it’s part of the inscription, IVN).

  • Your inscription may begin with IMP (“imperator”) or DN (“dominus noster”). Bear in mind that a caesar won’t rate the title of IMP at the beginning of the inscription or AVG at the end, so if you have either of these elements, you definitely have a sitting emperor. DN is sometimes used with caesars.

  • Sometimes the first part of an inscription includes abbreviated forenames such as FL (Flavius) or CL (Claudius). These may be helpful to you in the final stretch, but they’re more likely to be a distraction in the early stages of cracking the inscription. Still, it’s useful to know what they are if you happen to have them.

  • Once you have looked at the very end and the very beginning and, with luck, have narrowed down the area where the main name is to be found, the next thing to look for is all or part of the letters CONST. The odds are in your favor that you’ll find them, since so many ACE coins originated with either Constantine the Great or his sons Constans, Constantine II, and Constantius II. (The other son, Crispus, is less often seen, and then only as a caesar.)

  • If you find CONST, the next thing to do is see if the name is short enough (count the bumps, if you can’t actually read the letters) to be CONSTANS.

  • If the name is too long to be CONSTANS, look for the telltale third N that distinguishes CONSTANTINVS from CONSTANTIVS. Failing that, count the bumps that used to be letters: 12 for Constantinus, 11 for Constantius.

  • If you know that you have CONSTANTIVS, the odds are extremely good that you have Constantius II (the son of Constantine the Great, whose coins are extremely common), rather than Constantius I (the father of Constantine the Great, whose coins are rarely if ever found in ACE lots).

  • If you know that you have CONSTANTINVS, the odds are very good that you have Constantine the Great, who ruled for many years, rather than his son Constantine II, who was emperor very briefly and caesar only slightly longer than that.

  • If you’re morally certain that there’s no CONST anywhere in your inscription, then you need to widen your search. Try VALEN (could be the beginning of either Valens or Valentinian), LICINIVS, and ARCADIVS for starters. Failing that, try PROBVS. Failing that, retrieve whatever individual letters you can. When you post the inscription to the ACEHelp board (especially with a picture), you’ll be amazed at what the experts can tell you, even with fragments.

  • If you can get your hands on a copy, a great print resource for obverse inscriptions is David Van Meter's Handbook of Roman Imperial Coins. Here you can find all the known variations of obverse inscriptions for each emperor, empress, and caesar, and can look up which obverse inscriptions are commonly combined with which reverses. Which leads us to the next major task:

6. Work on the reverse image next – The great news here is that there is only a limited number of common reverses found among ACE coins, and they’ve been lavishly detailed by Doug Smith in his Dirty Dozen file, which you can reach via the Teacher Resources button on the ACE home page.

! Note: to me, the learning curve dictates that the best place to start is with the obverse of the coin, because even if you can’t read any part of the inscription, you may be able to distinguish some of the details of the headgear and/or clothing and accessories, and if not that, you may at least be able to see that there’s a head and which way it’s facing. Another fallback position that’s very satisfying but stops well short of a complete ID is to figure out what type of reverse you have. On this side of the coin, as opposed to the obverse, if you can identify the design type you can probably also figure out the inscription, and vice versa. This is because with very few exceptions, each common reverse design found in ACE lots had a standard accompanying inscription.

Without trying to recapitulate Doug’s fine work, here are some shortcuts:

  • If there is no picture, but only some letters surrounded by a wreath (possibly also with an inscription surrounding the wreath), look at Doug’s # 9.

  • If you have a single figure, see if there’s a trace of a wing on the right side and something that might be a laurel wreath on the left. If so, look at Doug’s #10.

  • If you have a single figure but there’s no evidence of wing or wreath, try Doug’s #4 and #7. If you have #4, there may be a trace of a skirt on the figure and you’ll probably see the bump of the globe (with nothing on top) to the left. If you have the Jupiter variant of #7, there may be a tear-shaped blob on the lower left (Jupiter’s eagle) and the surviving line of his full-length scepter on the right. If you have the Sol variant, you may be able to see traces of rays around his head.

  • If you have two figures with what look like one or two shish-kebabs between them (actually battle standards, or signa), try Doug’s # 2.

  • If you have something that looks like two angels playing tennis, try Doug’s # 3. If your coin is difficult to read, you may still be able to detect a wing on each side and the two laurel wreaths (aka tennis racquets) in the middle.

  • If you have a very complicated reverse image with lots of curved lines, what my students and I call “scrambled eggs,” try Doug’s # 1. The elaborate design will be one tip-off, even if you can’t make out what it is. You may also be able to see the line of the spear with which the unfortunate horseman is being skewered.

  • If your reverse has a building on it, or if you can see anything that resembles rows of bricks or building blocks, check out Doug’s #8.

  • If your reverse has three figures, you probably have Doug’s #12.

  • If you can make out a sort of stair-step shape, ascending from left to right, try Doug’s #11.

  • The remaining two of the Dirty Dozen, numbers 5 and 6, are perhaps most easily recognized by the obverse.

When you begin to work on the reverse, the best thing to do is print out several copies of Doug’s article and use that for reference. In fact, this may be the place to put in a pitch for using as many hard-copy sources as possible, at least in the early stages of identification. The pictorial resources available on the ACE CD and on the Internet are terrific, but many students work better from books or printouts than they do when browsing on the computer.

7. Work back and forth between the reverse image and the reverse inscription (if any). Remember that if you can get all or part of the reverse inscription, you can probably identify the image. Conversely, if you can figure out the image, you will almost always know what the inscription was, even if it’s no longer readable. Thus, for instance, if you know you have two soldiers standing with one or two signa (aka shish-kebabs) between them, the accompanying inscription has to be GLORIA EXERCITVS. If you think you see a building, see if you can make out any part of PROVIDENTIAE AVGG as the inscription. Note that Doug’s #5 and #6 have no inscription on the reverse, #10 has three possibilities, and #9 is a special case.

8. Take a deep breath and tackle the mint mark – Like the inscription on the obverse, the mint mark is one of the most important clues to a complete coin identification. Also like the obverse inscription, the mint mark is unfortunately one of the most baffling parts of the coin when you’re just starting out. Basically, what you’re looking for is a sequence of several small letters at the bottom of the reverse (an area called the “exergue”). The sequence may start with P, M, or SM (“pecunia,” “moneta” or “sacra moneta”). It might also end with a letter indicating the particular officina, or workshop of the mint that made the coin. The middle part of the mint mark will indicate the name of the city where the coin was minted. Often this is a straightforward abbreviation such as ANT for Antioch. Sometimes, however, the abbreviation is less obvious, especially if the city had more than one name in antiquity. Then too, some cities have several variant mint marks. The best thing to do is go into it with an open mind, identify as many of the letters as you can, and see if you can find a match on the list of mint marks provided by ACE. Even a single letter may be enough to put the ACE experts on the right track, if you can also provide other information about the coin. The main thing is, don’t be tempted to skip the mint mark just because at first sight it looks like an undifferentiated blob. Not only is it an important clue to the coin’s identity, it also provides one of the most interesting pieces of background information about the coin – where it was made. Definitely worth the effort.

9. Look for anything else of interest on the reverse – Some coins have letters or symbols in the exergue or the flat area (the “field”) around the main figures. You may see an asterisk-shaped star, or a dot (a “pellet”). There might be a Greek letter. These details may not mean much to you or your students, but the ACE experts can often use them to help pin down an exact identification.

10. Scan the coin and upload the image to the ACEHelp site – It makes all the difference in the world to the ACE experts if they can see a picture to help with the attribution process. On the other hand, not all of us have easy access to a scanner or time to scan anywhere up to 25 coins, and some of us have no previous experience with scanners in any case. There may not be an ideal way to resolve this issue, but here are some things that might help at the teacher’s end:

  • In all but the youngest age groups, you may have one or more students who know all about scanners. Maybe you can delegate the job.

  • You have plenty of work to take home as it is, of course, but if you don’t mind doing the scanning at home and you have the equipment, it may be a lot easier to run through a batch of scans there than at school. Just remember to upload the images from there, too. More than once I’ve realized that I’d left the image file on my home computer and thus had no way to upload it to ACEHelp from school. Doh!

  • Two images are great, but one is much better than none. It may be that you can get a decent scan of only one side of the coin. That’s okay: just upload the good one.

  • Sometimes you can get a good image by pressing aluminum foil (the thinner and cheaper, the better) tightly over the coin and scanning it that way. I’ve never had much luck with pencil rubbings, but that’s another way you might try to get an image when the coin itself doesn’t scan well.

  • Your scanner will give you a chance to crop the image closely around the coin before you do the actual scan, to avoid scanning a huge area that’s too big to upload.

  • The ACE mavens will be looking at an enlarged image rather than the thumbnail that appears on the web page, so scan your images with a medium-range resolution setting and save them with low to medium compression (this will make sense once you start doing it). Otherwise, when the images are enlarged, they won’t be readable.

  • You don’t necessarily have to prop the coin up on a glass sheet, as the ACE tips suggest. If you can filch the glass from a small picture frame, by all means try it that way. But don’t feel you have to have the glass. It’s definitely worth a shot without it.

  • If you’ve never scanned anything more complicated than a sheet of paper or a photo before, the first few coins you do will take forever. When I started, each coin took around 20 minutes, and even then most of the images were awful. The images still aren’t anything to brag about, but after my second year, I was able to knock off most coins in about a minute. Take heart – it will get faster.

11). Get your students to fill out their data sheets as completely as possible. You might want to find the online submission form (linked to the ACE website) and print out hard copies for them to fill out before they go online – Unless your school has a mentor, you will probably be submitting queries to the ACEHelp board via the online submission form. Rather than have students sit down at the computer to extemporize their submissions, it’s a good idea to make sure ahead of time that their information is accurate and as complete as possible. Also, giving them a hard copy of the form at the beginning of the attribution process will help them understand what kind of information they're meant to be looking for as they work with their coin. (Incidentally, the process of communicating with the ACE experts offers a great chance to sneak in a little instruction on the difference between writing a courteous e-mail query and knocking out a heavily abbreviated, punctuation-free instant message or text message to friends.)

12). Get the most out of the ACE experts by giving them something to work with – If this sounds preachy, it isn’t meant to be. The truth is, though, that there’s a bare minimum of information that each student needs to have in hand before submitting a query, or it’s going to be essentially a frustrating and time-wasting exercise all around.


  • The most basic thing: quantitative data. Every student can provide his or her name (with only an initial for the last name), the school’s name, and the school’s user name for the ACEHelp board. Every submission can include the coin’s diameter in millimeters. If you can possibly get access to a scale, it will also help a lot to provide the weight.

  • If humanly possible, provide a scan.

  • I’ll go out on a limb (and I’m not in any way speaking officially for ACE here) to suggest a couple of fallback goals to shoot for if you can’t get a complete identification. If you can read enough of the obverse to tell which way the head is facing and what type of headgear it has, that’s something. If you can read enough of the reverse to tell what general type of design you have (and remember that from that you’ll probably know what the reverse inscription is, if there is one), that’s even better. If you’ve met either or both of those goals, the information you can provide from that, along with the quantitative data – and ideally, images – will give the ACEHelp folks a starting point and will make it worth your time and theirs to submit a query. You’re going to want to aim higher than that, to at least tackle the obverse inscription and the mint mark, but if you can get a handle on the obverse image or better yet, the type of reverse, or even better still, both, that’s a pretty darned respectable result for a teacher and student working without a mentor.

  • Based on the preliminary information you provide, the ACEHelp experts may be able to give you suggestions that will allow you to figure out additional information about the coin. Not only do they know a lot more about this stuff than we do; they also have access to reference works that we don't have.

That’s it! Relax, have fun, and don’t hesitate to ask for help or advice if you need it. It’s all, as the kids say, good.

Kate Gilbert

Ben Franklin Academy

Atlanta, GA