Procopius Coin School – Counterfeits and Replicas: Methods of Coin Counterfeiting
A coin may be made of real gold, it may be several hundred years old, and it may even come from an old collection – but none of this in itself proves that it is genuine. To determine its authenticity, it is also necessary to establish when it was made, using what technology, and under what circumstances.
Counterfeiting does not always involve the production of an entire coin. Simply altering the date or mint mark on a genuine coin can create an item that appears to be a valuable rarity. On other occasions, a replica originally produced for study or display purposes is passed off as an original on the market.
The history of forgery therefore also encompasses the history of copies. The purpose for which they are produced, the documentation relating to the object, and the designation used in its sale help to distinguish between the two.
The main methods and the associated deceptions
- Cast counterfeits.
- Counterfeit coins made using newly engraved dies.
- Moulds made using a pattern taken from the original coin.
- Electroformed replicas, electrotypes.
- Pieces made from a base metal core and plated with precious metal.
- Changing dates, coin marks and inscriptions.
- The subsequent re-engraving and „correction” of the coin’s design.
- Fantasy stories and fictional versions.
- Artificial ageing and the misleading presentation of the origin.
These methods may be combined. A cast piece may be re-engraved at a later date, a counterfeit coin may be artificially aged, and a false provenance may be attributed to an old copy at a later stage.
1. Cast counterfeits
When producing a cast counterfeit, a negative mould is taken from an original coin, and molten metal is then poured into the cavity thus formed. The solidified object mimics the surface of the original coin, but is not produced by the metal-forming process characteristic of coinage, which involves the application of pressure.
Gases trapped in the mould during casting and voids formed during solidification tiny casting holes, pits or irregular pores may result in. Other signs to look out for include a grainy surface and blurred details.
However, when assessing porosity, one must also take into account corrosion, the condition of the base material and any subsequent surface damage. A porous coin is not automatically a cast counterfeit.
Where the parts of the shape meet casting seam, and residues from the casting channel may form at the point where the metal was introduced. Once these have been removed, machining marks may remain on the rim.
It is always important to be familiar with the original manufacturing technique used for a particular type of coin. Some coins were originally cast; in such cases, the casting marks are natural.
2. Counterfeit coins made using newly engraved dies
These replicas are produced using dies made at a later date and by striking. The coin is therefore indeed a struck piece; however, this does not mean it is a product of the original period or mint. Carl Wilhelm Becker’s work is a notable historical example of this.
An important point of reference for this realisation is the distinct stylistic difference. The proportions of the portrait, the modelling of the face, the rhythm of the curls, the crown, the heraldic animal and the design of the ornamentation may differ from the characteristic styles of the workshop of that period.
The following deserve special attention the shape, thickness, slant and spacing of letters and numerals. The spacing between the motifs is just as important: how far apart the portrait is from the circular inscription, the coat of arms from the inscription, or the year from the border.
A forger may be able to reproduce individual details convincingly, whilst the proportions of the overall composition are distorted. The counterfeit coin may even appear more regular than the original.
There may be significant differences even amongst original, hand-engraved dies. The crucial question, therefore, is whether the details, taken together, are consistent with the known characteristics of the period, mint and die variant in question.
3. Die blocks made using a pattern taken from the original coin
In this method, the surface of a genuine coin is copied onto the counterfeit die. The image on the coin can thus be very close to the original, but any unique imperfections on the master die may also be transferred to the coins struck later.
One of the strongest points in support of this realisation is the identical, recurring wear and tear. If multiple items display scratches, dents or indentations in exactly the same place and of the same shape, this may suggest that they were copied from a common template. The coincidence of several independent marks is particularly telling.
It is important to distinguish between common die marks and damage caused by copying. On original coins, a die crack may, of course, occur repeatedly. However, knocks sustained whilst in circulation affect each individual coin separately.
When examining a coin, it is useful to compare it with several authentic examples and photographs from previous auctions. It is worth paying particular attention to the larger flat areas, where small indentations that do not form part of the coin’s design can be more easily distinguished.
A generally dull detail and unusual gilding may be cause for suspicion. However, a lack of vibrancy may also be caused by poor gilding or a worn-out original gilding tool.
Even here, the correct weight and metal content alone are not decisive. It is necessary to examine the surface, any recurring damage and the reference samples together.
4. Electroformed replicas, electrotypes
Galvanoplastics is a metal replica produced by electrochemical means. In the case of coins, the obverse and reverse are often reproduced separately, and the metal shells produced in this way are then joined together.
A galvanic description can be very detailed, so Examining the rim is particularly important. A fine joint line, or possibly a trace of solder, may remain where the two shells meet. You can try to conceal the joint by smoothing or filing it down afterwards.
The letters may appear rounded and slightly thicker, and the details may be softer. Any unique imperfections on the sample piece may also be reproduced. The weight and density may differ from the original, although there may be exceptions.
A galvanic replica is not necessarily intended for fraudulent purposes. Such replicas were also produced for display in museums and for comparison.
An old copy may have its own historical significance. Deception occurs when it is passed off as genuine currency whilst concealing the fact that it is a copy.
5. Items made from a foreign metal core and plated with precious metal
The essence of the method is that the core of the coin is made of a cheaper metal, whilst its surface is coated with a layer of precious metal. In ancient numismatics, such coins, often fourrée Coins bearing this designation are important artefacts relating to counterfeiting of the period. Museum collections also preserve counterfeit coins from that era and objects associated with withdrawn coins.
During the inspection, the continuity of the coating, any exposed metal at damaged areas and the physical characteristics must be assessed. However, a discoloured patch may also be the result of corrosion or contamination; therefore, it is not advisable to draw conclusions based on colour alone.
Counterfeiters of that era exploited the monetary value of the currency. In contrast, later collectors who produce counterfeits primarily count on the premium derived from the item’s rarity.
A contemporary forgery may be a valuable historical artefact, but the correct term for it remains contemporary forgery.
6. Changing dates, mint marks and inscriptions
The counterfeiter starts with a genuine coin. By altering the year or mint mark, they attempt to turn a common coin into a valuable rarity.
A good example from our collection practice Franz Joseph’s 5-korona coin from 1906, in which the numerals on original coins from other years are replaced or altered. We have already come across this kind of alteration on the 10-korona note from 1915.
These may be counterfeit coins, as the coin itself is genuine; it is only the year, which determines its value, that has been altered.
The digits needed for recognition their shape, height, thickness, inclination and distance from one another This needs to be examined. It is also important to consider how they are attached to the surface of the coin.
Smoothing of the surrounding surface, signs of machining or a difference in colour may arouse suspicion. In the case of inserted digits, the edge of the join also warrants attention. When identifying altered dates, a comparison of the die marks with those on authentic examples can also be helpful.
Minor discrepancies in the numerals may also arise from the original die versions. The shapes of the letters and numerals, their positioning and the condition of the surrounding surface must all be assessed together.
The money may be genuine, whilst the year on it is false.
7. The subsequent re-striking and „correction” of coin designs”
During post-processing, worn or damaged details are re-etched into the metal. The aim may be to improve the appearance or to create a special version.
The examination should focus on determining whether the condition of the details is consistent with that of the surrounding surface. Strikingly sharp hairline details or artificially deepened ornamentation on a heavily worn portrait warrant further investigation.
A treated coin may be an original specimen, but its surface no longer retains the original condition of the strike. The NGC also distinguishes between misleading alterations to the date and mint mark and other types of surface treatment.
Any alterations must be disclosed at the time of sale so that the collector is aware of the coin’s actual condition.
8. Fantasy stories and fictional versions
A fantasy coin is a historical-style creation that does not replicate an authentically verified contemporary issue. It may combine existing motifs or give the impression of a denomination that was never actually issued.
Items made of unusual materials, of exceptional weight or previously unknown specimens must be examined with particular care. A gold coin modelled on the design of a silver coin cannot be classified as a contemporary trial strike on the basis of its material alone.
In order to identify an object, historical and numismatic evidence is also required in addition to the object itself: previous publications, collection records, links to mints, or documents shedding light on the circumstances of its issue.
The claim that it is a „previously unknown rarity” is not, in itself, supported by its absence from the catalogues.
9. Artificial ageing and the misleading presentation of origin
The surface of a counterfeit coin may also be altered to give the impression that it is an old coin. Artificial discolouration may divert attention from flaws in the counterfeit coin’s details; the NGC has documented such an example.
The story associated with the item may also influence the buyer. Claims such as „from an old estate”, „from Grandfather’s collection” or „of museum origin” constitute unverified provenance without supporting documentation.
A forgery may well have found its way into an old collection, where it may have been regarded as genuine for several generations.
A long history in a collection is part of the object’s history, but does not in itself prove the authenticity of its issue.
Counterfeit, copy and reissue
When naming a work, both the circumstances of its creation and the manner of its presentation must be taken into account.
- Copy: a reproduction of a previous object, identified as a copy.
- Reprint: subsequent beating; in order to assess this, the origin of the sticks used and the circumstances of their manufacture must be clarified.
- Contemporary forgery: an unauthorised imitation produced whilst the original currency was still in circulation.
- Collectors’ forgery: a later replica sold as, or intended to be, an original historical artefact.
- Fantasy series: A work of a historical nature, but depicting a contemporary type that has not been authentically verified.
The term „replica” does not in itself prove official origin. Moreover, a copy may later become a means of deception if its true nature is concealed.
Paduaners: Renaissance-era reproductions of ancient coins
The Paduan artists form a notable group of Renaissance-era imitators of Roman coin designs. Their best-known master was the Paduan Giovanni da Cavino (1500–1570) was.
This interest in antiquity also inspired the creation of new works. Cavino’s works should therefore not automatically be equated with forgeries produced with the intention to deceive. The specialist literature also emphasises this distinction. At the same time, due to their convincing appearance, they may later have been mistaken for genuine Roman coins
There are also later reproductions associated with this group. The British Museum also holds a later copy of this Renaissance imitation.
In the case of a „Paduaner”, it is therefore also necessary to clarify whether we are referring to a Renaissance work or a later copy of it.
Carl Wilhelm Becker: Counterfeit coins from the early 19th century
Becker produced high-quality forgeries using his own dies. He also sold his works through dealers, but in 1824 he was forced to admit to his activities. After his death, further copies were produced using his engraving tools. His surviving tools are preserved in a museum collection.
When referring to the „Becker-style” designation, the date of manufacture and the accompanying documentation are therefore important. The history of a piece produced during the master’s lifetime may differ from that of a piece produced later using his dies.
Today, these are collectable artefacts from the history of counterfeiting. However, their intrinsic value does not make them genuine ancient coins.
Adolf Resch and replicas of Transylvanian coins
Adolf Resch, a jeweller and numismatist from Brașov, is known for his seminal work on Transylvanian coins, the Published in 1901 Transylvanian Coins and Medals from 1538 to the Present Day is related to the volume entitled
Resch also produced electrotyped replicas. The literature on him mentions his collection of reproductions of Transylvanian coins and medals. His work fits within the context of collecting and research practices at the turn of the 19th and 20th centuries.
It is therefore not appropriate to simply equate his work with that of Becker. The production of copies also served a documentary and scholarly purpose.
However, the term „Resch copy” is a specific attribution: not every old Transylvanian electrotype can be proven to be his work. Identification requires documentation and comparison.
For the collector
When assessing originality, three issues must be considered separately:
- What is the subject? Genuine currency, a contemporary forgery, a later copy or a fantasy coin?
- When and how was it made? The year shown on it does not necessarily correspond to the date of manufacture.
- What sort of procedure was performed on him? Even a genuine banknote may bear a false year or altered details.
The weight, size, material, obverse design and edge must all be assessed together. No single characteristic on its own proves authenticity, and no single irregularity is always sufficient to conclude that a coin is a forgery.
An old copy may have intrinsic numismatic value. An accurate description enables the collector to purchase exactly what the item actually is.
Literature and specialist sources
Key works on history:
- Hill, George Francis: Becker the Counterfeiter. Vol. I–II. London: Spink & Son, 1924–1925. A fundamental study of Becker’s work and his coinage.
- Pinder, Moritz: The Becker counterfeits. Berlin, 1843. An early analysis of Becker’s counterfeit coins.
- Lawrence, Richard Hoe: Medals by Giovanni Cavino, known as “the Paduan”. New York, 1883. A historical catalogue of Cavino’s works.
- Klawans, Zander H.: Imitations and Inventions of Roman Coins. 1977. A study of imitations and fictitious types of Roman coins. The British Museum’s object descriptions also refer to it.
- Resch, Adolf: Transylvanian Coins and Medals from 1538 to the Present Day. Hermannstadt: Franz Michaelis, 1901. A Basic Catalogue of Transylvanian Banknotes and Coins.
The examples relating to the 5-korona coin of Franz Joseph from 1906 and the 10-korona coin from 1915 are based on Procopius’s practical observations; we do not provide a separate case study from the literature on these here.