One of the most common threads on this and seemingly every other ancient coin forum is: “is this real?” Experts can often answer that question by glancing at the coin. But how do they know? In a hobby where the opinions of experts literally determines what is real (valuable) vs fake (worthless), you’d hope there would be more to it than, “looks OK to me.” There is. A lot more to it. While an expert can process all the factors in his or her head, some folks (me) need help. So I compiled a list of factors to consider when rendering a judgement of whether a coin is real or not. It has helped me avoid buying countless fakes over the years. I hope it helps you. A few words about what follows. It isn’t intended to be a checklist. Going through the entire list for every coin I am considering buying would ruin the fun for me. I do tend to skim the list when evaluating a coin from an unknown seller, on eBay for instance, just make sure I haven’t missed anything obvious. Once a dealer is on my Naughty or Nice list, I no longer check each coin from that dealer. Most of the items on the list I learned from experts who generously shared their expertise. To them I am forever grateful. A handful of techniques are, I hesitate to say, my own, at least to the extent that I have not seen that particular technique mentioned anywhere else. Feel free to correct mistakes and add your own techniques. The comments are intentionally terse, so if something is unclear please let me know. Dealers Check notorious fake seller lists (from Forvm Ancient Coins, Wayne Etsy, etc) Google for negative seller mentions on forums Ask about the dealer in *ancient* coin forums Check dealer inventory for fakes Scrutinize dealers from “forgery school” regions of Eastern Europe and the Middle East Scrutinize material outside the dealer’s primary area of expertise (artifacts from coin dealers, coins from artifact dealers, ancient coins from modern coin dealers, “estate finds”, “grandfather’s collection”, “consignments”, etc) Scrutinize consigned coins if the dealer has not personally examined them Good dealers offer (and honor!) a lifetime authenticity guarantee eBay Only consider amount of *ancient* coin feedback *as seller* See what other things feedback givers have bought and from whom (if only coins purchased are from this seller, wonder why) Look for evidence of feedback manipulation (many cheap items sold, a few buyers who are all repeat buyers, same buyer buys the expensive items, etc) Look for evidence of hacked/sold account with a lot of old positive feedback Check recent auctions for evidence of shill bidding Avoid private auctions Avoid “returns not accepted” Avoid “cannot be returned if removed from holder” Scrutinize sellers from or sourcing from “forgery school” regions of Eastern Europe and Middle East, and antiquity embargo countries Common Sense “Too good to be true”: it is Sellers exporting from countries with severe antiquities trafficking penalties Rarities at absurdly low prices Missing, incomplete, or inaccurate descriptions Multiple misattributed coins (potential bargain or lack of seller knowledge/care?) Common coins listed as “RARE!” (marketing ploy or lack of seller knowledge?) Perfectly centered designs on perfectly round flans are extremely rare outside of fakes Gut Feel - if you doubt it pre-purchase, you will doubt it post-purchase Known Fakes Check if a known fake (use Forvm’s fake reports, ForgeryNetwork, etc) Provenance - ask dealer (some dealers won’t share because then you’ll know what they paid; ask again after sale) Provenance - use acsearch, etc to see if you can find this coin from prior sales by reputable ancients dealers/auction houses Die matches - use acsearch, Wildwinds, etc to find; die matches are uncommon except for rare coins with few dies; a die match by itself neither condemns nor authenticates a coin Defects Precision Perfection - beware if most valuable feature(s) of the coin (inscription, portrait, reverse design) are in the best shape; fakes rarely include defects to important details Defect Location - fakes rarely have defects that draw the eye away from the valuable details Deposits - deposits in depressions should match those elsewhere on the coin Corrosion - uneven corrosion is to be expected; perfectly even corrosion is a warning sign of artificial aging Concretions - copper chlorides: Atacamite and Paratacamite (bronze disease) are rarely introduced to fakes Concretions - copper oxides: Cuprite and Tenorite (brown or reddish crust) can be artificially induced Concretions - copper carbonates: Malachite and Azurite - hard dark green and blue crust suggests age; light green may be recent Concretions - copper acetates: verdigris is rarely introduced to fakes Patina Uneven patination is normal for a naturally patinated coin; perfectly even patination may be artificial Scrutinize rainbow toning Weight Weight outside the reasonable range for that issue is a bad sign (check similar coins for ranges, published papers about the coin) Weight loss inconsistent with amount of wear and degree of corrosion is a bad sign (guideline: slick, uncorroded US silver coins are 8% underweight) Dimensions Size should be consistent with other coins of same type, subject to centering of strike Thickness - normal size but over thick suggests base metal fake Uneven dies and flans and tilted strikes are the norm: thickness of coin will rarely be uniform around the entire perimeter Wear Check for consistency of wear between the obverse and the reverse Check for consistency of wear at different points of similar relief on the coin Coins do not wear evenly like a bar of soap, they wear preferentially on the high points while lower areas stay sharp Manipulations (tooling, smoothing) can be used to hide evidence of casting Worn coins should show dents, scratches from use Wear, dents, scratches, bumps should not all appear to have occurred at the same time Scratches - except for modern damage, the texture of dents and scratches should be consistent with the overall wear of coin (rounded edges if coin worn, etc) Test Cuts - edges should have wear consistent with rest of coin Test Cuts - no extra material inside cut Test Cuts - test cut cross-section consistent with being made by cutting tool Test Cuts - do not remove material so weight should be unaffected Fabric Clogging - metal clogging letters and small details can be a sign of casting Mushiness - real coins have sharp edges between devices and fields; should not gently flow together Flow Lines - should extend radially from high reliefs to fields or edges Pit Shape - circular or oval pits suggest casting bubbles; corrosion pits will be irregular rather than smoothly rounded Pit Edges/Bottom - from casting will be smooth; from corrosion will be rough Bumps/ridges - raised defects could be dents and scratches on a coin used to make the casting mold Appearance of modern minting with perfect surfaces is a warning sign Recrystallization - should be consistent with composition, usually high silver% coins; rarely/(never?) in debased AR, billon, AV, or AE Rims Wear of rims should be consistent with wear of rest of coin Excess material such as rim burrs or rim cuds are sign of modern minting Edges Presence of ridges or seams or lines or sprue on edge suggest casting Partial Collar - seen in ancient coin means electrotype Filing signs (scratches), retouching, polishing along edge suggests attempt to hide casting artifacts Electrotypes will have a weld line where the two halves were joined Round or oval holes or bubbles on edge suggest casting Level of wear and tone of edges should be consistent with that of the rest of the coin Cracks Presence of cracks can be a good sign Rough and sharp edges are good sign Smooth and blunt crack surfaces suggest casting Thin cracks are a good sign Cracks with extra metal inside bad sign Style Design - check thickness of features, shape of details, areas between details (use other coins of same type or from same period and location) Lettering - check font style, forming of serifs, how letters were cut, type of tool used to engrave letters into die (use other coins of same type or from same period and location) Ask Ask dealers, coin forums, etc. You can’t authenticate from photos, but obvious fakes stand out Ask Before Purchase: if even one person doubts the authenticity, you’ll never get that suspicion out of your mind no matter how many say it is real Non-Destructive Tests Lead swabs - Alexandria AEs, Republic bronzes, overweight Roman orichalcum sestertius, etc should test positive for lead; early Imperial bronzes, most ARs, etc should not Silver slide - large silvers should be slowed Ring Test - may work if coin isn’t corroded or recrystallized Specific Gravity - compare to composition range from research papers XRF - test metal composition at jewelry store, pawn shop, etc. and compare to known good coins, research paper results (may charge since uses consumables) Authentication Harlan Berk sticker service - free NGC - $25+ David Sear - $45+
Wow, that's quite a list! Good effort . See also https://www.cointalk.com/threads/ancient-coins-beginners’-faq-thread.324858/page-2#post-3222342 for links to resources teaching how to detect fakes, databases of fake coins, etc. Warren Esty, aka CoinTalk's @Valentinian CoinTalk has an excellent search engine. It is a very good idea to first search for the seller by name here (only after you have checked the Forum Ancient Coins Notorious Fakes Seller List and Warren Esty's Fake Seller list, otherwise we'll end up with a bunch of unnecessary posts). Bear in mind that a 100% positive feedback score does not ensure that the dealer is knowledgable or reputable. It depends on the coin type. Die matches are common among Roman Provincial coins. Sometimes you can even find die matches for one side to multiple reverses. I'm not sure I agree with this. Sometimes fakes are deliberately vague on certain details, and sellers push the coin as a lesser type, hoping someone who has just enough knowledge to be dangerous will think he has spotted a rarity that the seller missed. Perhaps you've made more of a study of this than have I, but it seems that almost any patina, oxide, or encrustation can be mimicked by an adept forger. Verdigris seems particularly easy to recreate. Although, in the absence of other diagnostic indications, "artificial" toning does not mean the coin must be fake. For an interesting discussion about toning see this thread. I'm not sure if this translates to coins which in most cases were buried for centuries. Various metals leach out; porosity can reduce weight beyond simple wear. Some series of coins do tend to be more consistent in their weight, particularly silver coins of greater fineness (Athens tetradrachm, for instance). Coins made with debased metal seem to suffer greater variations in weights due to burial conditions, if not also due to their starting weight. But bear in mind that the obverse and reverse dies wore out at different rates. A fresh obverse die may be seen with a worn reverse die, for instance, so you have to discern between die wear and coin wear. But keep in mind that flans are often cast, so remnants of sprues are perfectly normal on some coins. Some flans also underwent further shaping and preparation which cause tool marks (lathe marks on the surfaces; file marks on the edges), so you need to know the norm for flan preparation for the type of coin in question. The ring test is generally not advisable because ancient silver coins are embrittled to various degrees and may be more fragile than you realize. Worth saying again: At this point in time, no third parties offer guarantees of authenticity (meaning guaranteed authenticity of coins they did not sell to you). Having said that, all three of these entities are well respected and knowledgable. The best defense against buying a fake is always "know the coin or know the seller".
While I see many good points here and on TIF's reply, the big one is that is is often easy to KNOW that a coin is fake from photos or a quick examination but having the same degree of certainty assuring a coin is genuine is harder. Fakes come in all levels from 'tourist trash' to things that have fooled experts. There are people that LOVE to find fakes that slipped by the professionals and even collect evidence like that NFA catalog XXII with the fake aureus on the cover (oops!). We do the best we can but we all make the occasional mistake. Threads like this can o good but can be dangerous if they give anyone a swelled head about their abilities.
@TIF Thanks for all the great feedback! I’m always looking to improve my skills. I’ll update my list accordingly. A few comments: *Warren* Etsy - Doh! Sorry Warren Die Matches are a whole subject unto themselves. My point in the list is that die matches to even a known fake aren’t necessarily diagnostic, if the fake was made from a real coin. If have seen a die match used to prove authenticity or to condemn a coin; in and of itself it does neither, except in cases where a given die is known exclusively from fakes. I will add a new line item about vague details being used to “upgrade” a questionable coin. That’s a good one! I personally use my list to determine seller trustworthiness, which I find less time consuming than worrying about each coin individually. Upgrading questionable coins, applying fake patinas, inflating positive feedback, shill bidding, and similar sharp practices doesn’t mean the seller would sell a fake, but it says enough about the seller for me to move on. I am a student of artificial aging techniques used on fakes. My line items on these, like everything else in the list, are things to consider when forming an opinion. If I see a nice hard malachite and azurite patina *in the right sequence* I conclude either the faker has studied mineralogy (unlikely), or the encrustation is real (likely). The oxides aren’t diagnostic either way. I have not (yet) seen a fake coin with active bronze disease, for whatever that’s worth. You make an excellent point about die wear affecting perceived obverse and reverse circulation wear differences. That would be especially difficult to discern on a worn coin. I have noticed fakes sometimes are more worn and flawed on the less valuable side, while the valuable side is inconsistently sharper. Signs of casting are only a bad sign for coins that aren’t supposed to be cast. I should have made that clearer. Thanks again for the feedback!
I started my list years ago after seeing a dealer condemn a coin with a glance. When pressed, he couldn’t say exactly what was wrong with it, but he was as certain as you can be about these things that it was fake. My list is an attempt to quantify what you folks do in your heads, a skill even 50 years on I have not mastered. The hardest thing for me is style. It’s apparantly a dead giveaway when it is wrong (ultimately I concluded that is what the dealer had done), but developing the eye for that has eluded me. Ultimately, I think facial recognition software techniques can and will be applied to coins and art, and faking style will become a lot harder. I also expect a few surprises for coins presently in collections.
I would love to spend a weekend at a dealer/museum/wherever examining fakes. I wonder if the ANS has a black cabinet? Someday I'd like to visit their vaults.
I recall reading a masters thesis about counterfeit ancient coins. The author reported many dealers maintained black cabinets, though they were reticent to reveal that to collectors for fear of overstating the problem. I hope the ANA would share if they had such a thing.
I have seen so far some black cabinets of auction houses and they were very disappointing! At another forum someone has posted a link to black cabinet of Harlan J. Berk Link is from here : http://www.numismatikforum.de/viewtopic.php?f=6&t=11495&p=496877&hilit=facebook#p496877 https://www.facebook.com/aaron.berk.3110/videos/275482376519435/ The Harlan J. Berk fake collection is very impressive I have never seen so many bad cast fakes, Tourist fakes and British Museum electrotypes at one places ^^ The only fake of him I am really jealous of is the NGC SLABBED Tryphon Tetradrachm which is ex Harlan J. Berk and was withdrawn at Stacks Bowers auction this year ^^ It is still a very obvious fake but I like Tryphon tetradrachms even if there is like here the emperors name wrongly written ^^ https://auctions.stacksbowers.com/lots/view/3-BGG6H
To be of use, a Black Museum has to have the fakes well documented explaining the type fake being shown. Too often we see comments on fakes that show someone just does not understand the question. Style is important but casts copy the style of the original so it is pointless to say you don't like the style when the style is not the problem. Conversely, fake dies cut by modern hands (Slavey, Lippanoff, Becker etc.) produce struck coins without any sign of being cast. Then we get into cases where dies were used but show signs of being applied by pressing rather than striking or where the dies were cut using rotary tools that left tell tale marks even though the hammering and flan preparation were spot on. A drawer full of certain fakes needs to be studied every bit as much as our real coins if they are to give us any degree of protection. That still leaves the matter of whether we consider coins made in ancient times to be genuine 'ancient coins' even if they were made outside the regular official mint. How do we tell the difference between a 'branch' mint coin and a product of a ancient counterfeiter? The study of fakes might just be as complex as the study of the coins themselves.
The ANS has a black cabinet. Last year I visited to attend their seminar on counterfeits. I snapped pictures of the Black Sea Hoard dies which are a special interest of mine. https://digitalhn.blogspot.com/2017/09/black-sea-hoard-dies.html Ute Wartenberg explained that the best way to recognize counterfeits is to practice with the real coins, not with the fakes. If you practice with the fakes you may learn the style of an individual counterfeiter. I was lucky to attend the ANS seminar on counterfeits and also all of the seminars from the ISBCC (International Bureau for the Suppression of Counterfeit Coins) during the years when they had open meetings at the New York International. (They still have meetings at the New York International but it is no longer possible to attend except as an IAPN dealer. If anyone can make me an honorary dealer for a day let me know). My trick to detecting counterfeits is knowing what genuine coins look like at different magnifications. The coin should look genuine at a distance, up close, with 10x, and with 15x loupes. Very few coins look good at all of these magnifications.
"If you practice with the fakes you may learn the style of an individual counterfeiter." The style of counterfeits will not be that helpful but if you know that most fakes from modern dies are pressed and how to detect pressed fakes (by knowing the difference between pressed and struck coins) you can easily aviod many fakes from maaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaany different counterfeiters!!!!!!! "Ute Wartenberg explained that the best way to recognize counterfeits is to practice with the real coins, not with the fakes." I do not think that this is true and complete nonsense ! I can better authenticate coins than many dealers and experts of auction houses who have handled so many thousand coins within the years in hand. And it is not like I would be a genius or something special I only know what to look for and others can learn the same if they invest some time to study fake coins and some time to study authentic coins, the more talent the less time is required. To get beyond this level is of course very difficult and this is my problem because the ones who are beyond this level are not in such boards or forums and will not share their knowledge and skills with everyone. I can very often authenticate coin I am not familar with easily because I know the typical problems of fakes and almost all fakes do have this problems more or less. Fakes are always in a certain way different from authentic coins! So it helps of course if you are familiar with ancient coins. Fakes will be often altered to hide problems, which is already a warn singnal if a coin is altered. Or stupidity of forgers impossible die links (different mints and emperors) or coin hoards with for example aurei of different emperors but all coins from one emperor from one very fresh pair of dies and no die links to authentic examples. Or they place fakes into coin hoards before they were placed at market and this fakes do not always make sense in this hoards (dates of the coins or geography ...). If they use ancient coins as planchets it can be detected , too. Artificial patina is different than authentic patina so bronze fakes can be detected easily if the original patina is still there... There are 3 different kind of fakes: Cast fakes have specific problems and can be easily detected in pictures and in hand if you know what to look for. Electrotype fakes have specific problems and can be easily detected in pictures and in hand if you know what to look for. Transfer die fakes and fakes from recutted transfer dies have specific problems and can be easily detected in pictures and in hand if you know what to look for. Struck or pressed ... This first 3 have problems in common, for example detail loss and transfer errors and softer details than the mother and individual characteristic from the mother and details if recutted (in mould or dies) are often different than they were in the authentic dies and can be detected with die studies. Modern die fakes have specific problems and can be easily detected in pictures and in hand if you know what to look for. Struck or pressed ... It is not only style it can be flan shape, weight, alloy composition, die axis, or other emission specific characteristicas of this emission. Here knowledge about authentic examples of this emission is helpful.
Perhaps you could teach us your techniques. Post some fakes that you have detected in dealer catalogs and show us how you exposed them. I am curious.
Maybe you Look at forumancientcoins for Din X or at forgerynetwork for Amentia! You want to challenge me, challenge accepted. Who else? Some more recent Greek fakes here http://www.numismatikforum.de/viewtopic.php?f=49&t=53721&start=360 Or published Theodosius solidus correctly for sale here http://www.numismatikforum.de/viewtopic.php?f=6&t=11495&start=6660 My best recent catches within the last 6 months 7. November I posted to Forvm Valentinian Medallion of 2 Soildi"Starting Price: 12 000 EUR" It was a Slavey Replica you can check by yourself if you have the paper catalogue of them, coin was withdrawn with picture https://www.forumancientcoins.com/board/index.php?topic=117085.0 https://www.numisbids.com/n.php?p=lot&sid=2858&lot=448 And Leu cover coin Constantine I, Medallion of four Siliquae Estimated price was 30000 SFR and coin was withdrawn I posted it to forum on September 26, 2018, 09:30:03 am https://www.forumancientcoins.com/board/index.php?topic=116770.0 It was posted to CFDL on 15. October so it was clearly my catch because I have posted it already more than 2 weeks before to FORVM and he could have read it there and reposted it to CFDL or found out by himslef 2 weeks later than me, we do not know and it does not matter, I have posted it first. https://groups.yahoo.com/neo/groups/CoinForgeryDiscussionList/conversations/messages/38027 https://www.numisbids.com/n.php?p=lot&sid=2776&lot=285 Julian II solidus Ric 99a transfer dies fakes + mother https://www.forumancientcoins.com/board/index.php?topic=115586.0 NGC Slabbed Tryphon Estimate: $10000.00- $15000.00 coin was withdrawn https://www.forumancientcoins.com/board/index.php?topic=116245.0 https://auctions.stacksbowers.com/lots/view/3-BGG6H
I want to encourage collectors to learn how to detect fakes by themself because humans make mistakes and dealers and and experts of auction houses are humans too. Yes some dealers have managed to offer no fakes or at least no fakes I am aware of and some auction houses even manage to have complete auction catalogues without fakes so it is not impossible. Others have a significant higher nuber of fakes in catalogue or to offer. I have written often enough how to detect fakes so I will not do again but the knowledge is in internet available. 4 Eyes see more than 2 and the more eyes the better, the more people who are cleaning them market from fakes and support dealers and auction houses the better. The coins suspected as fakes should be of course really fakes because if not it would hurt the reputation of a reputable auction house or dealer and that would not be ok. And most dealers and experts from auction houses are really kind persons and they maybe only had a bad day and not enough sleep before deadline or the coin had a good pedigree or came form a very good collection and they are then really happy if they will be notified. A dealer and an owner of a very small auciton house even offered me a reward or better a discount for my next purchase, I of course rejected to this was really a nice offer and I do not have the intention to hurt such good and kind people!!! It is much more effective if collectors and Dealers and Experts of auction houses know how to avoid fakes, this would reduce the number of fakes in the market and would be good for our hobby. Some problems of fakes can not be avoided and other problems which can be avoided will casue other problems. And yes not all do have enough time to learn this and then it is of course right to rely on the skills of reputable auction houses and dealers or authentication services. Almost all fakes at the market can be detected with some knowledge easily, yes the really expensive fakes can be really hard and to be honest many of them would fool me too but there are luckily enough Experts who are able to detect them so that they will not be offered or withdrawn. Of course many are much better in detecting fakes than me but you will not find them in internet and if you still find them they will not tell you how to get beyond my level. I never pretended to be the best or one of the best but when I see so ("many") fake in the market offered on ebay or by dealers or auction houses it is frustrating and hurts because most of them are very obvious fakes. Everyone can achieve my level or even better if he invests enough time in studying fake and authentic coins.
@Lolli That withdrawn slabbed coin is wholely remarkable. Between the photos, the slab, and the provenance I wouldn't have given authenticity a second thought. For once I'm glad not to have been able to bid on a coin worth more than my entire collection.
