CHAPTER EIGHT
Many factors must be considered when arriving at the value of a Roman coin on the collector market. Fortunately, most of these factors involve tangible and intangible aspects that are second nature to collectors, and thus are easy to understand. Why would most collectors prefer a coin of Julius Caesar over one of Trebonianus Gallus? Why would most prefer a coin of fine style over one of crude style, or one which is perfectly preserved over one which is heavily worn? Though the answers to these questions come easily, the many factors which help us arrive at these conclusions do not. The discussion of value determination will fall into two sections: the first will concern the attributes of coins themselves, and the second will examine aspects of the marketplace. In the discussions which follow, the phrase all other things being equal must always be borne in mind. Indeed, this phrase means exactly what it says ó that absolutely all factors but the one being examined are equal. We may first examine the stages in the ìlifeî of a Roman coin, each of which can either positively or negatively affect the appearance of a coin. The four stages are:
I. Coin Production (The Planchet, The Dies, The Striking Process)
II. Circulation and the Use in Ancient Times
III. Burial
IV. Recovery, Conservation and Subsequent Effects
I. COIN PRODUCTION
Ia. The Planchet
Metal Quality This aspect is determined before the coin is even struck, and is generally uniform within a particular issue. The metal most prone to debasement in Roman coinage history was silver. While weight standards fluctuated with gold, the purity rarely deviated by more than 5%. The reduction in the purity of silver demonstrates the slow decline in the prosperity of the Empire. Silver that has been alloyed with a significant amount of base metal is far more likely to be adversely affected by burial in the ground than is nearly pure silver. Thus, debased silver coins generally are not as appealing as those of the highest purity.
ìSilveringî This process of coating the surface of a base metal coin with a thin wash of silver was a common practice at the Roman mints in the late 3rd and the 4th Centuries A.D. The goal was to identify the coins as part of the precious metal series in a time when silver was not available in sufficient quantities to produce coinage of good silver. This ìsilveringî was thin and was applied by different methods of varying effectiveness. Research suggests that a process called ìblanchingî may have been commonly employed. A planchet of base metal alloyed with trace amounts of silver would be immersed in acids that affected copper, but not silver. As a result, a thin silver shell would remain on the surface, which would then be bonded to the base metal core when the planchet was struck. Very often these ìsilveredî coins emerge from the soil in a poor state, and are corroded unevenly. Therefore evenly silvered coins command a premium.
Planchet size Though the size of planchets tended to be fairly uniform within an issue, they sometimes varied considerably. Planchet size can be measured in terms of weight, thickness and diameter. In an ideal world the planchet would be thick enough and broad enough for the entire design on the die to be represented on the coin. The degree to which this was achieved affects the market value of a coin. For some issues it is commonplace to have a full planchet, and in others the planchets are usually too small to encompass the whole design. Naturally, collectors are attracted to coins which are well-centered on broad planchets, preferably with excess metal beyond the scope of the dies. Coins so blessed will always sell for a premium, and if they combine these assets with a planchet of unusual heaviness, they are often classified as ìtrial piecesî or ìmedallicî strikings, at least in a commercial sense.
Planchet flaws A wide variety of defects on the planchet can affect the final appearance of the coin. Some of these defects are obliterated in the striking process, whereas others are only amplified. The most common flaws are listed below.
ïLaminations: Improper planchet production can result in a thin layer of metal detaching from the surface either while or after a coin is struck. If the detached piece was present when the coin was struck, it will bear the design impressed by the part of the die with which it came into contact. When it separates from the rest of the coin, a shallow (usually uneven) deficit results. Fortunately, laminations are usually isolated to a small area of the coinís surface.
ïImpurities: The ideal planchet is homogeneous in content, and when this is not the case (either because air or some other impurity exists in the planchet) problems can result. Planchet impurities often survive the striking process and remain undetected even during the circulation life of a coin, only to be exposed after the coin has endured centuries of burial. This occurs because different substances oxidize at different rates, and thus the impurities will oxidize either slower or faster than the rest of the coin.
ïStriations: These are lines incised on the planchet (or occasionally on the struck coin) by a file or similar tool. Striations can be divided into two major categories. The first is ìadjustment marks,î which were made to reduce the weight of a planchet or to remove surface irregularities which might damage the dies. Striations are more often visible on base metal coins since gold and silver are softer, and thus traces of file marks were easier to obliterate in the striking process. The second category of striations might best be called ìcutting marks,î as they were caused when planchets were separated from one another during their production.
ïMisshapen planchets: Rarely are the planchets of ancient coins perfectly round. Indeed, more often they are slightly oval, squared, or simply irregular. These defects ó unless they are so unusual as to be charming ó inevitably reduce the collector value of the coin. They most significantly reduce value if important parts of the design or inscriptions are affected.
ïCracks: This topic is discussed later in the text (since it is more often related to the striking process), but is mentioned here because the cracks sometimes occur during planchet preparation.
Ib. The Dies
Style This is the most difficult category to define, for what appeals to one person may not appeal to another. Let it suffice to say, however, that among those who have made a careful study of ancient art, there exist parameters for defining style, be it fine style, average style or poor style. Imperial coinage is diverse in its appearance based on where and when it was struck. Dies cut by local artisans in Asia Minor have stylistic peculiarities which make them easy to distinguish from the products of Rome, Illyricum, North Africa, Gaul or Spain. Sometimes the best products of a certain period were produced in Rome (such as with the portraits of the emperors Galba and Vitellius), and other times some of the most engaging portraits were engraved at Ephesus or Antioch (especially under the Flavians). To become familiar with the different categories of style, and the levels of quality within those categories, it is best to consult as many books and catalogs as possible, including those which discuss other forms of art, such as sculpture, gem-cutting, etc. In terms of the marketplace, it all becomes quite simple: all other things being equal, coins of good style command higher prices than those of lesser style. In later periods of Roman history, where style becomes less of a consideration, it will usually have a less significant effect on value as compared with earlier times.
Relief Directly related to the work of the die engraver is the relief (or depth) of the images. The raised parts of the design are properly called the devices, and all of the flat area is referred to as the field. Devices include not only the principal design element (a portrait, or deity, etc.) but also the inscription and any border design. All other things being equal, a coin of high relief will be more valuable than a coin of low relief because of the sculptural effect that is achieved. Usually the price difference is significant because high relief is obvious even to the untrained eye, and often it transforms what might otherwise be a bland image into an impressive work of art.
Die State A die is capable of producing the crispest image in the earliest stages of its use. Indeed, with each successive strike, a die loses sharpness of detail. Even if a coin is perfectly struck, the details of a design cannot be transferred to the surface of a coin if they do not exist on the die. Several aspects of die state are discussed below.
ïFresh die: The best impressions are made with freshly-cut dies, for they-have all of the detail that the artist originally engraved. If the fields of a coin have little or no evidence of die flow (see below) and the devices are sharply detailed, it was struck with dies which had not seen much use. Sometimes a coin was struck with one fresh die and another which was severely worn (as is commonly observed on double-denarii of the mid-3rd Century). The existence of a circular ìguide lineî (incised on the die, raised on the coin) sometimes is a good indication that a die was in an early state. This circle ó which apparently was not used in every case ó was probably the first thing cut into the die, for it helped the engravers cut the inscription in an orderly manner and center the design. Since the ìguide lineî was often only intended as a temporary guide (and thus was engraved lightly), it tended to disappear after a modest amount of use. Other times, the cut is deliberately deep, and is of little use in this exercise, for it survived well into the life of the die.
ïWorn or eroded die: A die which has been used well into its ideal lifespan will show the effects by producing images of reduced clarity. The weak details on coins struck with worn dies are often mistaken for circulation wear or simply a soft strike. Indeed, a coin can be fully lustrous, but only have the detail of a coin grading Very Fine. A common effect of excessive die use is the presence of ìflow lines,î which are etched into the die by the flowing metal of the planchet, which flows rapidly when struck. These flow lines are damage to the die and are reproduced in the form of raised lines in the fields that radiate from the center toward the edges. Since die production was time-consuming, expensive and required the expertise of both artists and metallurgists, it was not uncommon for dies to be used past their ideal lifespan.
ïCracked die: One of the most severe forms of damage to a die is a crack, which can range from a small defect in the lettering or dotted border to a heavy crack that goes from edge to edge. Cracks and splits are incused in the die, and thus are represented on the surface of the coin as ridges of raised metal. A related defect is a ìdie bulgeî that perhaps originated as a chip in the die. The contours of die bulges are usually smooth, indicating they were polished by the mint workers, or became smooth from strike friction. Die cracks and bulges affect the value of the coin in direct proportion to their seriousness. This includes not only the size of the defect, but its location.
ïRusted die: Occasionally (it would seem) a die would be put aside while other dies were employed. If not properly protected from exposure to oxygen, these dies (usually made of iron) would rust. When the dies were reconditioned for use, the rust would be polished off, but small pits would remain. These are reproduced on the surface of a coin as irregular areas of raised metal.
ïPolished die: Before dies were put into service (and periodically during their lifetime) their surfaces were polished with an abrasive substance to remove impurities and minor defects. This routine maintenance prevented small problems from becoming more serious. Since the devices ó the recessed areas of the die ó were beneath the flat surface, they tended to remain ìfrostyî while the flat area (which created the fields on the coin) was more highly polished.
ïRe-cut or re-worked die: This was a fairly common part of die maintenance. If an area of the die was losing detail, or had become damaged, the die would often be repaired rather than discarded. Repairs were made with some minor polishing or tooling, and under other more serious circumstances might involve re-cutting or modifying the original design. Sometimes re-cutting occured to correct an error made by the original die cutter(s).
Ic. The Striking Process
This is the principal act in the minting process. The various effects and defects associated with this process are discussed below.
Luster: When a coin is struck, the metal is compressed between the dies. In reaction to this force, the metal expands and flows directly outward from the center. This rapid flow of metal occurs in a split-second, and makes tiny incisions on the surface of the die, which result in raised ridges of metal too small to be seen individually with the naked eye (when this is excessive, the flow lines can become large and distracting, as discussed above). Collectively they create a visual effect called luster by reflecting light at various angles. It is important to note that luster occurs only on coins struck with slightly worn dies; when the dies are freshly polished (as discussed above) the surfaces are endowed with a brilliant, mirror effect. Though luster more properly belongs with the discussions of die characteristics, it is discussed under the striking process as a matter of convenience.
Centering: Though perfect centering is commonplace on modern coins, it is very much the exception for ancient coins. A small degree of de-centering, from about 5% or 15%, is normal and should be expected from almost any hand-struck coinage. Minor de-centering does not significantly affect the value of Roman coins if it is in the correct direction. For example, if it clips the tip of the emperorís nose, or decapitates the deity on the reverse, then it will significantly reduce market value. However, if it simply shifts the design 5% toward the back of the head, leaving some extra space before the portrait, the value of the coin should not be affected to any significant degree (and in some cases may even be enhanced). However, perfectly centered coins are the most desired by collectors, and as such they command a premium.
Strength: This refers to the crispness of the strike. Coins which are sharply struck bring a premium (sometimes a significant premium) above those which have average or weak strikes. Coins that are softly struck are less attractive because the fine die details will either be weak or totally absent. If the area of insufficient strike is large, the surface may exhibit the roughness of the unstruck planchet.
Evenness: This factor is independent of centering or strength of strike, as it is determined by the angle at which the dies impact the planchet. Unevenly struck coins exhibit a sharp strike on one portion of a coin and a weak strike on the opposing portion. If the faces of the die are aligned parallel to the planchet, it allows the force of the strike to be evenly distributed, assuring no area of the design suffers from an insufficient strike. Uneven strikes can reduce the value of a coin significantly, especially if the weakness occurs in an important area of the design.
Multiple strikes: It almost always took more than one blow of the hammer to strike an ancient coin, no matter how shallow the relief. This left ample opportunity for the dies (or the planchet) to shift between blows of the hammer. Nearly every ancient coin probably did shift slightly between strikings, but the subsequent blows were strong enough to obliterate any trace of this. In extreme cases this shifting caused spectacular errors (see the discussion below), but more often it resulted only in slight ìdoubling.î Multiple strikes are betrayed by a ìshadowî of the outline of a design and can sometimes greatly reduce value.
Planchet Cracks: The main cause of planchet cracks is the temperature. If the planchet was not heated to the proper temperature while being prepared, and again before being struck, then it was probable that the planchet would crack upon striking. If the metal is not fluid enough to flow when the pressure of the blow is delivered, it releases its energy by cracking, rather than flowing. Cracks are always wider at the edge of the coin than they are where they terminate inward. Planchet cracks range from small ìhairlineî fissures that might be visible only on one side of the coin, to deep cracks that go completely through to the other side and sometimes extend inward beyond the center of the coin. If a crack is deep and severe, it greatly affects value, especially if the location is unfortunate. If a crack is well hidden in the bust of the emperor it will not impact the market value as greatly as one that affects the portrait. Sometimes (especially under the Flavians and the Adoptive emperors) edge cracks on sestertii were closed by mint workers who hammered the edge of the coin at the point of the crack. While it does seal the crack, it also flattens the edge and pinches the rim.
Overstriking: As a measure of practicality (or necessity), Roman mints would sometimes use existing coins from circulation as planchets for new issues. The best practice in this case would be to melt the coins completely and cast new planchets from the bullion, but this was not always a practical option. Alternatively, the old coins could be hammered or filed until the old design was virtually obliterated. Indeed, if a coin was overstruck properly, no traces of the design of the host coin would survive the re-coining. When traces of overstriking do exist, they can be quantified in terms of how much of each design exists; in other words, how much of the design of the host coin (called the undertype) remains visible compared with the new design (the overtype)? Needless to say, this varies considerably. Overstriking is especially evident on cistophori struck by Hadrian at mints in Asia Minor. Value is affected negatively if the undertype adversely affects an artistic coin, but value can be enhanced if there is some academic importance to the overstriking.
Errors: Because Roman Imperial coins were hand-struck, minor imperfections are to be expected. In some cases they were produced with such carelessness that they must be categorized as ìerrorî coins. An interesting error will often increase the value of a common coin, but it will greatly reduce the price of a coin that otherwise would be of exceptional value for its artistry or rarity. The categories of errors most commonly encountered on Roman coins are described below.
ïDouble Strike: Severely double-struck coins ó where a second image is shifted considerably to one side or another or is rotated to a different position from the first ó are seldom encountered. Usually the result is so unattractive that it renders the coin virtually uncollectible, but other times it can create an interesting appearance, and thus enhance the value of a coin.
ïFlip strike: This error occurs when a planchet turns over between blows of the hammer, resulting in the images of both dies being impressed on both sides of the coin. The most recent blow tends to obliterate most details of the earlier strike, though enough traces will exist such that it can be determined that this error occurred in the striking process.
ïOff-Center Strike: While moderate de-centering is very common on Roman coins (and, indeed, should be expected), some are struck 30% or more off center, and this is unusual. Although the values of such coins are not necessarily increased with this defect, they sometimes are collectible as oddities.
ïBrockage Strike: A ìbrockageî striking occurs when a coin that is already struck adheres to one of the dies (usually to the reverse die, which is held in the minterís hand) and is not removed before another fresh planchet is placed between the dies. The result is that the fresh planchet receives the normal image from the clear die, and an incused impression of that very same design from the coin that is stuck to the opposite die. This is a relatively common error on denarii of the Roman Republic, and is perhaps the most dramatic of all errors found on ancient coins. Only very rarely will a brockage feature the reverse design.
ïClashed dies: Occasionally the dies are hammered together when there is no planchet between to absorb the impact. As a result of the dies clashing, a ìshadowî of the designs of each die, called ìclash marks,î will be faintly impressed onto the die opposite. Most coins subsequently struck from these ìclashed diesî will reflect the damage in their images. This is an especially common occurrence on denarii of the Severans, where faint outlines of the obverse bust can be seen in the otherwise-blank fields of the reverse.
ïìMulesî: Many times in the history of Roman coinage, dies that were not originally intended to be matched were used together, either by mistake or as a measure of practicality. Such coins can be of value to the researcher, for they sometimes shed light on conditions at mints (or outside the mint, as many of these, no doubt, were struck by profiteering mint workers on their own time).
II. CIRCULATION AND USE IN ANCIENT TIMES
Wear: This effect is the most natural for a coin; it is indicative of the purpose of its manufacture. Since wear is the byproduct of the stripping of surface metal over a long period of time, it tends to be evenly distributed and affects the highest points of the design first. Even on heavily worn coins the metal in the recesses of the design is largely protected from wear. As such, you may expect to find luster in the protected areas of some gold and silver coins even though they may be only Very Fine.
Countermarks and Counterstamps: Technically, these are forms of damage to the ìhostî coin, but they always had a practical purpose that is of historical interest. Most often they were applied to re-value an issue, redefine its area of circulation, extend circulation life, or to propagandize a change in regime. Countermarks most often take the form of an incuse rectangle or circle containing a raised design, but sometimes they are much more elaborate. Since countermarks were applied by hammering a punch into the coinís surface. This often would crack the coin if the countermark was applied near the edge. But more often the damage would be limited to flattening the original design on the opposite side of the coin. Most often countermarks were applied to base metal coins circulating in the provinces, whether they were provincial or Imperial. Only vary rarely are gold coins countermarked, but silver coins of the 1st Centuries B.C. and A.D. were sometimes countermarked, notably in the East by Vespasian. In the late 5th or early 6th Centuries A.D., the Ostrogoths or the Vandals ìcutî the value markings XLII or LXXXIII into the surfaces issues of Roman middle bronzes and sestertii (mostly of the 1st century A.D.) to revalidate the antique ìhostî coins with current denominations.
Test cuts and ìBankerís Marksî: These forms of damage were applied by people who presumably were suspicious that a coin was a forgery. They were applied at Rome mainly in the late Republic and early Empire, though they are far more common with Greek coins. They are only observed on precious metal coins. A test cut was applied by a chisel or other edged instrument, and was usually delivered with the blow of a hammer. Bankerís marks were also created by a hammer blow, but the tool was a punch with a narrow tip engraved with a design or shape. Although punch marks are usually shallow (just deep enough to penetrate the silver plating), test cuts can be so deep as to sever a coin. Some coins have more than a dozen bankerís marks, which indicates that they may have been used for more than merely determining if the specimen was counterfeit, but perhaps also to demonstrate that the coin was acceptable to the party who applied the mark.
III. BURIAL
Patination: Certain aspects of the ancient coin market are especially subjective. One such aspect is patination, which is the often colorful result of the way the surface of a coin has reacted with the chemical environment of the soil in which it was buried. Results range from the spectacular to horrific, with copper-based coinages being most severely affected. On bronzes of similar rarity and state of preservation, patination is usually the most important factor in determining its value to collectors.
Patination is not limited to copper-based coins. Indeed, silver coins are also severely affected by burial, although the patination is usually removed in a chemical bath. The closest thing to a patina for gold coins is encrusted earth in the recesses of the design, or perhaps a reddish toning resulting from the oxidization of the copper in the alloy. The latter can often be attractive, and is especially desirable on first century aurei that came from the ìBoscorealeî find near Pompeii.
Most experienced collectors can recognize a high-quality patina, but few will agree on what is the best kind of patina. Perhaps the most popular kind is a slightly glossy medium green patina on bronze. Especially prized by some collectors are extremely pale green, gray or blue patinas, which sometimes are nearly white. However, the design details are especially hard to see when a patina has this pale shade, so the coin must be tilted to the best angle to be seen clearly. Thus, this definitely is an acquired taste. Also popular are brown patinas, which range from tan to dark chocolate, and are the kind most often encountered. Another popular surface condition for a bronze is the virtual lack of a patina, which sometimes occurs when a coin is buried in the silt of a riverbed or in clay deposits. An exampie of this is popularly known as a ìTiber patina,î and is so-named because coins and other metal objects that have been buried for thousands of years in the silt of the Tiber River often have these characteristics. More often than not, though, a bronze has no patina because it has been subjected to an acid cleaning ó with the result not being very pleasing to the eye.
Especially important in patination is the consistency of both color and texture (which usually vary on the surface of a single coin). Patinas of inconsistent coloration are sometimes called ìmottledî; those with inconsistent texture are often called ìrough,î ìgrainy,î ìporous,î ìpittedî or ìencrusted.î The texture of a patina can further be classified as ìglossyî or ìmatteî depending on how it reflects or absorbs light. It is also important to remember that some patinas are more stable than others, and that the harder patinas are more desirable. A sestertius that grades Extremely Fine, but with pitted surfaces and a rough, multi-colored patina is worth considerably less than one which is only Very Fine but has a smooth, glossy emerald green patina. This is the main reason the values stated in this book for copper-based coins must be interpreted with great caution, for they are meant to represent coins which fall somewhere between the two descriptions just presented. The values in this book are for absolutely average surface conditions ó in other words, for coins that are not affected either negatively or positively by their patination.
Porosity, corrosion, pitting, crystallization: This damage to the surface of a coin always lowers its value to collectors, usually considerably. Porosity can range from the barely noticeable (often called ìslightly grainyî) to damage so severe that the details of the coin are rendered illegible. The effects sometimes cover the entire surface evenly, but are equally likely to affect only isolated areas.
Encrustation: Also very common to ancient coinage is encrustation. Unlike porosity (which is recessed), encrustation is raised. Nearly every ancient coin is somewhat encrusted from its burial, raising the question of how much of the encrustation can be safely removed. Sometimes encrustation is so hard and solidly attached to the surface that removing it would cause significant damage, and so it remains.
ìHorn Silveringî: A common effect on silver coins is ìhorn silvering,î which often occurs when silver coins are buried together, and the chemical elements of the soil leach silver from one coin and re-deposit it in a modified form on the neighboring coin. This chemical process occurs over centuries, and can be quite damaging to the appearance and value of a coin.
ìBronze Diseaseî: This is an active form of deterioration of the surface (and often the interior) of a copper-based coin. Unless it is neutralized, and then stabilized, it may spread rapidly and continue to transform the copper into a powdery green byproduct. Bronze disease is very light green in color and (unlike a patina) is soft and powdery. As such, it is easy to recognize. Bronze disease usually can be ìcuredî through a series of soakings in distilled water, but this should be done by someone who is experienced in such procedures, otherwise the disease will probably recur. Damage already done, of course, cannot be reversed.
IV. RECOVERY, CONSERVATION AND SUBSEQUENT EFFECTS
Most ancient coins emerge from the earth more closely resembling a rock or a charcoal briquette than the lustrous or finely patinated objects which we so admire. The process of turning one of these encrusted lumps into a presentable coin is often called the art of conservation.
It is important to recognize that virtually all ancient coins have been cleaned after being unearthed. The cleaning may range from a mild soap bath to remove dirt from gold coins (which are often unaffected by long-term burial) to intensive chemical or mechanical processes for severely encrusted coins. The conservation process may be broken down into the initial phase of cleaning, in which most of the debris is removed, and the secondary phase of conditioning, in which the more detailed cleaning occurs. In the case of a coin excavated decades or centuries ago, the conditioning process may occur in ever-finer gradations over several generations.
Proper and ethical cleaning requires talent, technical expertise, experience and patience. Of course, ìcleanersî will always have different levels of skill, and different concepts of what is acceptable. Even the best cleaners had to begin somewhere, and inevitably they made many mistakes before they mastered their art.
A frequent complaint is that many coins are over-cleaned. However, this is nothing new. The reason older, pedigreed coins may have a more pleasant appearance is that they may have been able to recover from this process over several decades or centuries. The ìcabinet toningî that accumulates on a coinís surface over the years often makes the ill effects of an old cleaning less objectionable. Illustrations of turn-of-the-century auction catalogs are not of the coins themselves, but plaster casts of the coins, which do not accurately represent the surface condition, so collectors may rest assured that most of those coins are not as perfect as they appear. The main aspects of conservation are discussed in the section that follows.
Cleaning: This process will range from a mild treatment to a rigorous process involving chemical and mechanical components. Every ancient coin that is fully visible ó whether in a museum, an auction, or a private collection ó has presumably been cleaned. Gold coins may only need to be washed in a mild detergent, whereas a silver coin salvaged from a shipwreck may require intensive care. The goal of cleaning is to return the coin as much as possible to how it appeared before it was buried. This rule is slightly different for copper-based coins, where the additional goal of preserving the patination (which certainly did not exist before it was buried) may also exist.
In an ideal world, everyone who cleaned a coin would be highly skilled and exercise restraint and good judgment ó but this certainly is not the case. It is important to remember that every time you see an attractive ancient coin you are witnessing the work of a (hopefully) skilled cleaner.
Toning: To be strictly accurate, toning represents an erosion of the coinís surface, and technically it is damage. This erosion occurs on a microscopic level and thus may not be significant. However, its effects on the appearance of the coin are often considerable, whether it is created over decades or artificially in a few moments. Attractive toning often increases the value of a coin, or at the very least makes a coin more desirable as compared to an untoned or unattractively toned coin. Catalog descriptions will sometimes refer to the toning as ìold collection toningî or ìcabinet toning,î since many coins from old collections have acquired an even coating from spending many decades in wood and felt coin trays.
Pin scratches: These are often referred to in catalog descriptions, and are the result of over-zealous effort to remove surface dirt or encrustation with a sharp object. In the process, the metal of the coin is damaged, and the value of the item is decreased considerably. Faint scratches are often called ìhairlinesî or ìhairline scratches.î
Waxing or lacquering: Although still done occasionally, applying a thin layer of wax or lacquer to the surface of coin is largely a technique of antiquarians of the past. The purpose was to isolate the surface of the coin from oxygen, which in some instances could prove harmful, especially if the air was humid. One notable collector who did this was the late King Farouk of Egypt. More recently, this procedure has been frowned upon because of its effect on the appearance of the coin. Additionally, some lacquers or waxes will become ìfoggyî over time, making it more difficult to appreciate a coinís beauty.
Exceptional Damage: This section includes a number of undesirable defects that occurred both in ancient and modern times. Incidental defects that result from normal use in circulation or are inflicted as a result of careless excavation are not described.
ïëDamnatioí: One of the most interesting forms of damage to ancient coins is ìdamnatio,î which was an expression of emotion, be it a personal or a sanctioned act. When deceased emperors were despised by the public or condemned by the new regime, a period followed wherein the effigies and inscriptions of the deceased were systematically destroyed. This principally included sculptures, monumental inscriptions and monuments, but it also included coins. Obviously this practice was not entirely effective (at least on coinage), since coins from some of the most hated emperors survive in large quantities. The damnatio memoriae usually involved the recall of coinage of the targeted emperor, and in more extreme cases, resulted in the chiseling of the portraits or inscriptions on coins still in circulation. The most remarkable instance of this defamation occurs on numerous coins of Caligula (for the letter ìCî representing his name was purposely removed), and on certain provincial coins that bore the confronted portraits of the emperors Geta and Caracalla. When it was learned that Caracalla had murdered his brother Geta, some authorities apparently recalled the coins and with chisel cuts ìerasedî both the portraits of Geta and the portion of the inscriptions that named him. The coins were then released back into circulation, making a statement that no doubt was as potent in the 3rd Century as it is today.
ïGraffito (pl. Graffiti): Coins sometimes were ëinscribedí by their owners in ancient times for a variety of reasons. In some cases it was merely out of boredom, but at other times a graffito represents a political or religious statement, a sign of ownership, or an attempt to transform a coin into a magical amulet. In modern times, it may mark a coin as the property of the finder, and often takes the form of a simple ìXî in the field. Graffiti usually reduce the value of a coin considerably.
ïFiling, clipping and other forms of metal removal: In modern times, this form of damage is usually caused by an attempt to re-shape the coin so it will fit into jewelry. Though this occurred in ancient times for the same purpose, it was more commonly done by a culprit who kept the excess metal that was removed and who returned the coin to circulation at full value. Another ingenious method of removing metal from coins was to put them into a bag containing sharp metal shavings. The bag would be shaken vigorously and the metal shavings would remove tiny pieces of metal from the surface of the coin. At dayís end there would be a profitable pile of gold shavings at the bottom of the bag. Clipping of siliquae in 4th and 5th Century Britain was done to specific weight standards, and current theory holds that the clipping was supervised by some central authority to create reduced denominations.
ïGilding: In ancient times this technique was commonly used for utilitarian and decorative objects of every type, with the obvious advantage being a great savings in the amount of precious metal used. On coins it most often occurred on medallions or contorniates. Gilding is different from silvering (see discussion above). In this process a thin coat of precious metal is applied to the whole surface, or specific parts of the surface of a coin. Modern gilding is usually done by those who hope to pass base-metal coins as precious metal pieces, or by jewelers who want to achieve the decorative effect of a gold or silver coin while only paying for one of a less costly metal.
ïSmoothing and Tooling: Both of these practices are commonly applied to ancient copper, bronze and brass coins, and occasionally to precious metal coins. Because of the effects of oxidization on coins, they often emerge from the earth with pits or encrustation (see the discussion above). The desire to smooth out these rough areas and create a more pleasing object hails back to the Renaissance, when collecting the objects of ancient Greece and Rome became fashionable. When encrustation is expertly removed without damaging the metal, it can greatly improve a coinís appearance. To qualify as ìsmoothingî the work should be limited to the fields of the coin. When it is also applied to the devices, or is done with severity in the fields, it must be classified as ìtooling,î which is the more serious form of this procedure. Finally, when it goes beyond aesthetics, and into deception, it is termed re-engraving (see below).
ïRe-engraving: This is essentially the same as smoothing and tooling, except that it is more often done to change the identification of the coin than to enhance its appearance. It is usually done in modern times by a knowledgeable party to increase the clarity of design details, or to fictionalize elements of the design (to turn a common coin into a more valuable one). In ancient times this would have been an extraordinary occurrence for the purposes of commercial gain, but it was done to erase images or inscriptions of emperors who were out of favor (see above, damnatio) or to alter the images for any number of other reasons.
ïInlays: This is a severe form of damage which, like most other categories of damage, occurred both in ancient and modern times. In the ancient world, inlays were commonly applied to the privately issued contorniates of the late Empire, and were rarely applied to coins to transform them into decorative objects, tokens, counters or into amulets with a variety of applications. In modern times inlays have sometimes been used to identify coins belonging to a particular collection. The most famous example is the silver eagle-on-shield traditionally attributed to the DíEste family, but which has recently been re-attributed to the Gonzaga family. The inlaid Gonzaga coins fetch a significant premium over what the coins would sell for without this attribute.
ïEx-Jewelry: Coins had been used in jewelry for several centuries before the foundation of the Roman Empire, and like a great many practices of the Greeks, the Romans followed suit. This ancient tradition has also been popular in modern times. When coins are put into bezels, attached to pendants or contained in any other way, they are likely to be damaged in the process. Typical signs of damage from inclusion in jewelry include clipping, filing, scraping, soldering, piercing, harsh cleaning or the appearance of ìmount marks.î The value of ìex-jewelryî coins will be reduced in accordance with the degree of damage and the merits of the coin itself.
ïTransformation into other objects: Though this obviously includes the use of coins in jewelry (as discussed above), it also applies to coins which were altered in ancient times for a variety of interesting reasons. Indeed, a small book could be written on this topic alone. The most common reasons for altering coins in the ancient world were to turn them into weights, counters for board games, etc. In these cases the original coins were filed down, re-shaped, inscribed. For a discussion of bronzes with hammered-up edges (to create a raised rim), see the entry for Æ Proto-contorniate in the denominations chapter. In other cases a coin was pierced so it could be nailed to a coffin or a wall for spiritual purposes, or to be suspended from the neck as a protective amulet. The idea that some sestertii or double sestertii were altered to be used as medallions in legionary standards is fanciful, as such ìmedallionsî were much larger than coins.
COUNTERFEITS
The art of detecting counterfeits is relatively complex at its most advanced level, and requires a mastery not only of minting technology, but also of the more subjective aspects of Roman coinage, such as style and fabric. Most counterfeits are either cast, struck or ìassembledî by attaching an obverse to a reverse. In all three of these categories the technology and skill level varies considerably from the crude and obvious to the extremely deceptive.
Some warning signs that a coin is counterfeit include the presence of air pockets in the surface, a general ìsoftnessî of detail extending into the areas of the design that should have been protected from wear, a lack of crispness where the devices meet the fields, a seam (raised or recessed) along the edge, a casting sprew that has been filed down, severe filing on the edge, a surface that is ìsoapyî to the touch, a coin that does not have the proper weight, diameter or stylistic appearance, or that shows no trace of corrosion, even under microscopic examination.
Precious little can be taught on this subject by mere words and pictures, so instead, only the categories of counterfeits will be discussed. It is important to remember that just as in grading, opinions about authenticity can and do vary among experts. The best defense against counterfeit coins is self-education, and being certain to make purchases from reputable dealers who are both knowledgeable and offer lifetime guarantees of authenticity. Purchasing coins in ìsourceî countries is not only risky from a legal standpoint, but quite often (no matter how convincing the ìcertificates of authenticityî may be) collectors can end up owning a counterfeit.
Ancient counterfeits: Counterfeit coins have probably been made since shortly after the invention of coinage in the 7th Century B.C. Since Roman coins came much later in the history of coinage, the art of counterfeiting was by then quite advanced, as evidenced by the large numbers of ancient counterfeits produced during the Republic and Empire. The main class of counterfeit ancient coins is the fourré, or plated coin, which was meant to resemble a coin of pure silver or gold but in reality had only a coat of precious metal over a core of base metal.
The plating on fourrés can remain intact even after many centuries of burial, but most often the base metal core has broken through at least in some portions, for it oxidizes at a faster rate than the precious metal shell. When it hasnít broken through, it is simply because the plating has adequately protected it from the corrosive elements of the soil. The vast majority of all fourrés were produced unofficially outside of Roman mints, but there is reason to believe that some were made at the mints either by profiteering mint workers or on order of the government itself so that it could to stretch its own resources during a time of crisis.
Issuing a coin that is considerably debased is only one small step away from issuing one that is plated, for the same motive is at hand. It is also possible that some plated counterfeits were struck with dies stolen from the mints, thus explaining why some of them are of such convincing style and manufacture.
At the very least this was done by Marc Antony, who struck many of his Legionary denarii in lower-quality silver, and of which large numbers of plated counterfeits survive. The original percentage of fourrés must have been quite high for the Legionary denarii, since during the course of decades of circulation the plated pieces no doubt were culled, leaving just the solid pieces in use.
In most cases the fourré can be identified by its weight, which is usually lower than that of even the lowest weight genuine specimen. In some cases the plating was so thin that the core became exposed in the course of circulation, for some that are unearthed do not bear a trace of precious metal coating. At other times the fraudulent coin was exposed by the application of a ìbankerís markî that broke through the plating and revealed the core.
Another kind of ancient counterfeit made in ancient times with the intention to profit by deception is the cast copy. Such copies were made of base metal or billon coins that were greatly overvalued in the market compared with the cost of production (just as is the case with modern coins). Thus, there was ample room for profit in their imitation. This was especially prevalent in Egypt, where the base metal and billon coins constituted most of the coinage, and circulated at an especially high rate within Egyptís closed economy. Indeed, forged billon tetradrachms and nummi are found with some frequency in hoards largely composed of genuine, government-issued pieces. Additionally, ancient clay molds bearing the impressions of such coins are known.
Another form of ancient counterfeit is the ìbarbaricî imitation that was presumably produced not with the intention of defrauding the recipient, but rather to remedy a coin shortage. This occurred most often in the far-flung provinces such as Spain, Britain and Gaul, but also occurred in almost every part of the Roman frontier from the 1st Century B.C. through the 4th Century A.D. Indeed, such imitations are known to have been produced in Arabia, India and even the island of Sri Lanka. The most common of these are the so-called ìbarbarous radiatesî which imitated the severely debased double denarii primarily of the 260s and 270s A.D.
Renaissance copies: Many of these were not created to deceive, but rather to make suitable replacements for coins that were excessively rare or unobtainable (such as sestertii of Otho, of which none are known to have been struck). Other times the motive for production was more sinister. They were original creations based on either the ancient prototypes, or on what the artist might expect a prototype to look like if it existed. Although sometimes these copies are fairly convincing, in general the style of engraving is different enough from the ancient coins so that they are easy to distinguish. The struck originals are remarkable antiques in their own right, and are thus highly collectible. ìAfter-castingsî of them are commonly encountered.
18th Century-early 20th Century copies: Unlike their Renaissance predecessors, most of these were made specifically to defraud the collector. They were usually struck from dies which were cut by the hand of a skilled artist. Four of the more famous counterfeiters were Becker, Caprara, Christodoulos and the ìGeneva forger.î Most of these coins are known and published ó and as such are seldom encountered in the marketplace, except as collectibles in their own right. Naturally, other forgers were active in this period, producing cast reproductions of authentic coins. Because they have acquired the ìcabinet toningî of their age, and often have impressive pedigrees, they sometimes are assumed genuine and are overlooked by catalogers.
Electrotypes: These are among the most deceiving counterfeits until the edges are examined. They are made of two thin shells of metal which replicate the obverse and reverse designs down to the sharpest detail. The shells are created by making a wax positive from a plaster negative of the original coin. The wax is then coated with a layer of copper in the electroplating process, after which the shells are given a thin coat of the appropriate precious metal.
Though the two shells may be used independently (for study purposes), they are often joined together at the edge, and the center cavity is filled with base metal. Many electrotypes were produced at the British Museum by Robert Ready, who stamped his initials into the edge. The easiest way to identify an electrotype is by examining its edge for the seam along the center, where the edges of the shells were fused together. The weight also is not usually accurate, and the initials of the maker may still be present.
Recent forgeries: A more recent breed of counterfeit is produced by making plastic dies from an original ancient coin and then using the dies to strike counterfeits. Since the style is exactly accurate on these die-struck counterfeits, the numismatist must rely on other aspects such as fabric, surface appearance, evidence of re-tooling of the die, and even an extremely close measuring of the devices on a suspected piece and an authentic coin that are believed to have come from the same dies. In other cases, counterfeits are produced by using advanced casting techniques. A third major category is the original method: producing hand-cut dies. Though some of the modern counterfeits are quite deceiving, most are ferreted out during the handling process from source to eventual buyer.
ìTourist Classî Forgeries: These are crudely cast items destined for the non-numismatist on holiday in lands where ancient coins once circulated. In fact, their crudity tends to give credibility to their alleged antiquity if the buyer has never handled authentic pieces. Most often, they are cast in base or ìpotî metal, even when the designs they copy belong to precious metal coinages. Sometimes the designs are ìmulesî of unrelated obverse and reverse types, or their designs are complete fabrications. The vast majority of all counterfeits belong to this category.
Altered coins: See the discussion under Re-engraving in section IV.