COIN GLASS

glassware usually in the form of wineglasses, goblets, or tankards enclosing a coin either in the foot, or in the hollow knop of the stem, rarely in an interior bulb. A Venetian specimen of coin glass dated 1647 is known, but the principal occurrence is in English glass from about 1650 onward. It was a useful device for expressing Jacobite or anti-Jacobite sympathies with either a Stuart or a Hanover coin. Early 19th-century loving cups and similar pieces in Boston glass generally had hollow stems enclosing coins. Roman coins, republic and empire The beginnings Although Roman coinage soon diverged from Greek conventions, its origins were similar. Rome, founded in the 8th century BC, had no true coinage until the 3rd. Roman historians later attributed coinage unhesitatingly to the much earlier regal period: some derived nummus (coin) from Numa Pompilius, by tradition Rome's second king, and Servius Tullius was credited with silver coinage, as well as with bronze stamped with the device of cattle. Roman historical tradition, however, seriously confused the elements of the true picture. Rough, unworked lumps of bronze (aes rude) were certainly used as a metal currency from the 6th century, if not much earlier, perhaps in rare conjunction with very small quantities of unworked gold and silver, themselves also passing by weight. Simultaneously, standards of value appear to have been expressed in terms of cattle and sheep, as is clear not only from the derivation of pecunia (money) from pecus (cattle, or sheep) but also from the early assessment of fines in oxen and sheep. From this it was falsely concluded that bronze coins marked with the device of cattle existed from the 6th century. In fact, the expression of values in terms of cattle may have lasted, officially, into the 5th century, for it was not until the decemvirs (a legislative commission) codified the law and drew up the Twelve Tables (451449 BC) that fines were fixed in bronze. This bronze still consisted of unworked lumps or, at most, rough bars of irregular weight. During the 4th century BC, Roman contact with the Greek cities of southern Italy slowly increased; these included such prolific mint cities as Nola, Hyria, and Naples. The coinages of these cities consisted of silver didrachms, of which Rome presumably made use in any necessary dealings with them. A hint is given, however, of widening Roman monetary interests by two issues of bronze token coinage. These, though certainly not produced at Rome, may perhaps be regarded as the earliest coins in the name of the Romans, struck at Naples c. 325285 within the terms of their alliance and intended for use in Campania, as distinct from Rome and Latium. It is unlikely, indeed, that a mint in the proper sense existed at Rome before 289, the year to which Pomponius assigned the establishment of tresviri (a board of three officials) who should be aeris flatores (bronze melters); and this mint (in the temple of Juno Moneta) did not yet produce true coins but aes signatum, bronze bars (of about six pounds) lacking a mark of value but bearing on each side a clearly recognizable type (including cattle) and perhaps equivalent in value to a Greek silver didrachm. These aes signatum bars were halfway between aes rude and true coinage. In 269 true coinage appeared. It consisted of aes grave, large circular cast coins of bronze all bearing marks of value, from the as (weighing one pound) down to its 12th, the uncia; the obverses showed the head of a deity, the reverses a ship's prow. These were paralleled at mints elsewhere by similar cast coins; their types showed not, as at Rome, Latin deities but rather Greek (in the south) or Umbrian and Oscan. At the same time, there appeared struck silver didrachms, on the standard of the Greek silver coins of Campania, bearing Greek types but marked ROMANO or ROMA. Accompanied by small struck bronze token coins, these were issued from Campanian mints, and they probably continued to the Second Punic War, terminating in a new issue of silver coins of Roman style and types (marked ROMA), including Jupiter in a quadriga (four-horse chariot) from which their name, quadrigati, derived; they were imitated in electrum by the Carthaginians in Capua. The quadrigati were of the weight of the lighter Romano-Campanian didrachms and reflected the rising cost of silver at a time of stress; concurrently the cast bronze coinage of Rome dropped steadily in weight from an as of one pound to one of three ounces or less. Financial stress is similarly to be seen in the exceptional issue of gold units and halves. Toward the end of the Second Punic War the quadrigati were replaced by silver coins of half their weight, with a Victory on the reverse, and hence called victoriates. By c. 190 a mainly silver coinage, Latin-inscribed, was in production at Rome and other authorized mints, accompanied by bronze coinage so greatly reduced in standard (and thus size) that it could at last be struck instead of being cast. Introduction of the denarius Adjustment of the previously fluctuating relationship between bronze and silver was first secured by the issue c. 211 BC of the silver denarius (marked Xi.e., 10 bronze asses), together with fractional coins, also of silver (marked Vi.e., five; and IISi.e., 2 1/2 assesa sesterce, or sestertius). The denarii were lighter than the quadrigati; their types were a Roma head on the obverse, with the Dioscuri (the twin deities Castor and Pollux) and ROMA on the reverse. Their production came to be confined principally to the mint of Rome. The victoriates, again lighter (their weight standard had come from Illyria), were issued until c. 150 BC, being perhaps intended for principal circulation outside Italy. The denarius, however, quickly established itself as the major currency in the central and western Mediterranean. In its eastward expansion, Rome learned to make use of local currenciesgold staters of Macedonia and silver tetradrachms of Athens or Asia. Rome was also prepared to employ Macedonian gold in the west, as was shown by the release to western markets of large quantities of gold staters after c. 150 BC. In the 2nd century BC, Roman coinage in gold was exceptional. Coinage in bronze, however, continued, but further variation in silverbronze values was seen in two developments. The as dropped in weight to that of an uncia and then less, becoming a token currency; together with its fractions, it was now always struck and not cast. The value of the denarius in terms of bronze was altered, being revalued c. 133 at 16 instead of 10 asses; the silver quinarius (now of eight asses and with the types of the victoriate) became rare; and the silver sesterce (now equal to four asses) virtually disappeared. After c. 80 BC the striking of bronze was discontinued until the time of Caesar. These developments mirrored the economic difficulties of the day. Reduction of the weight of the as from one to 1/2 ounce in 89 BC was accompanied temporarily by debasement of the denarius, resulting in the issue of denarii with serrated edges, intended to show that they were not plated. Techniques of production The essential advantage of using metals for currency, apart from durability, is that they can be shaped by melting and casting. Casting, therefore, has always been an integral part of the coin manufacturing process. Indeed, in some instances, it has been the only part. In early China bronze was cast into the form of the hoes and knives originally used for payment, and up to the 19th century the objects called cash, with their square central holes, were also cast. Similarly, the first Roman issues, aes grave (heavy bronze), were ponderous cast pieces, the heaviest actually corresponding in weight to the libra, the Roman pound. However, as soon as the state realized that it could make a profit from issuing coins by decreeing that their value in the market should be greater than the intrinsic value of their metal content, castingso simple an operationat once led to counterfeiting. Provided the mold was made from an official coin, there was no straightforward visual way of distinguishing true from false. For this reason, casting alone seems not to have been employed for precious metal currency. The prototype coinage of Greek Ionia on the west central coast of Anatolia in the 7th century BC consisted of pellets of electrum (a goldsilver alloy) made by pouring the molten metal onto the striated surface of an anvil, where, under the action of surface tension, they assumed a characteristic lenslike shape before solidification. The weight of the pellets was checked and confirmed for use by stamping them with a puncha naillike piece of metal, probably of bronze or iron. The punch sometimes had a crudely fractured end surface (which, of course, would be unique), sometimes an engraved design (the latter produced on the punch by drilling with abrasive corundum dust, which ate away at the surface, as in the lapping process perfected over millennia for sealstones). A counterfeiter would have had great difficulty in simulating the exact form of the punch surface. Within a short time, the issuing authorities began putting their own validating punch marks on the pellets, thus producing coins as opposed to bullion. In India before the Mauryan Empire (c. 321185 BC), currency consisted of small silver bars carrying as many as six marks; the boat-shaped silver emanating from Southeast Asia in the 19th century was also officially confirmed in this fashion. Ancient minting Most of the ancient dies that have survived are of bronze, although iron dies are thought to have been widely used also. Lower dies seem generally to have been disk-shaped so that they could sit in a recess on an anvil. In some instances the design may have been cut directly on the anvil. Engraving of the details was carried out using small steel tools (scorpers), or designs were drilled out using corundum dust. It is possible that major elements of the design were inserted by a hub, or master punch stamped into the die, but not all scholars accept that this method was employed in antiquity. Blanks or planchets (i.e., the small metal disks from which coins are made) seem first to have been cast by pouring the molten alloy from a crucible onto a flat surface, where they cooled into the characteristic lens shape. Later the metal was poured into molds, which sometimes consisted of two parts so that the metal was completely enclosed; traces of the flash, or joining line, can still be seen on surviving coins. At Alexandria in the Ptolemaic period (32330 BC), open molds were common; in these a sequence of disk-shaped impressions in the mold were connected by channels, and a number of blanks were thus obtained at one pouring. The upper surface of the blank, where slag and oxide accumulated, had to be turned off, or drilled out, presumably by a tool like a carpenter's bit, and the centre punch mark to accommodate the tool point is characteristic of Ptolemaic, Seleucid, and Greek imperial coins. Contemporary issues in India were often square in outline and were cut by chisel from metal sheets. Many Greek and Roman silver coins were plated; an envelope of silver sheet was soldered on a copper core, and it is by no means certain that all such specimens were the work of counterfeiters, since solid silver and plated coins sometimes appear to have been struck from the same dies. In the later Roman Empire (3rd century AD) silver issues were heavily debased with copper; prior to striking, the blanks were immersed in an acid bath that leached out the surface copper to expose more silver, giving a much more acceptable appearance to the coins when they were first issued. Strikingthe impression of the die designs on the blankswas startlingly simple. The lower die, set in the anvil, was covered by the blank; the upper die, which was positioned above, was then given one or more hammer blows. A two-pound hammer, wielded by one hand, could easily give a force at the die face of seven tons. To get the high relief typical of Greek issues, two or three blows were necessary, and often there is evidence of double-striking on the coins. However, by preheating the blank, as practiced in Athens in the 5th century BC, less force was required and die life was extended. Analysis of the documentary evidence implies that one obverse (lower) die could produce upward of 20,000 coins, while 10,000 coins have been struck from a simulated bronze die without significant deterioration of the working surface. Receiving the hammer blows more directly, the reverse (upper) dies enjoyed about half the life of the obverse. Production rates varied. In small mints, operated by one man, a rate of 100 coins per hour has been shown to have been feasible. At important centres such as Rome or Antioch teams of four probably operated. An eyewitness account of a Persian mint in the 1870s describes how, with a hammerer, a die holder, a blank placer, and a coin remover, one piece could be struck about every two seconds. The later medieval and modern coinages of continental Europe The change of power from Frankish to German emperors in the 10th century saw the silver denier extended into central and northern Europe. In the East the decay of the Byzantine Empire was reflected in the debasement of its gold coinage to electrum; after the temporary fall of Constantinople to Western crusaders in 1204, Byzantine tradition was carried on in the silver coinages of the derivative empires of Trebizond, Nicaea, and elsewhere. The revival of gold coinage in Italy in the 13th and 14th centuries, promptly copied elsewhere, led to the need for a silver denomination larger than the denier, and the grosso and its equivalents soon spread widely. From the 14th century coinage began to lose its Gothic stiffness: the Italian Renaissance pointed the way to naturalism in portraiture and to greater fluency of ornament. In the 15th century the first experiments were made with mechanical methods of coining, and by the 16th the new techniques were being generally adopted (see below Techniques of production). The traditionally privileged nonregal mints were incapable of producing the mechanical power needed for the intensive coinage not only of the large gold denominations resulting from the influx of Spanish-American treasure after 1493 but also with the equally large silver thalers, or dollars, beginning to be produced with silver from the German Joachimsthal mines. Multiplication of gold and silver coinages, and their larger denominational values, emphasized the need for token coinages, which were produced from the 17th century. Britain was effectively on the gold standard from the end of the 18th century, together with Portugal, but it was not until the second half of the 19th that continental Europe followed suit. Paper currencies of this period were fully redeemable in gold coin, but the gold standard was abandoned during World War I; since then, paper has been redeemable effectively only in base-metal alloys. The coin types of the later medieval period were relatively crude. Portraiture, schematically stiff on later Byzantine money, was revived with striking realism most notably in Renaissance Italy and thereafter flourished. Reverses revealed feudal influence in shields of arms and civic emblems. These developments set the general pattern of modern coinage, usually with an obverse portrait and some form of national badge or arms on the reverse. From c. 1800 onward this pattern was standardized to a large degree. Portugal Coinage began in Portugal, after the expulsion of the Moors, with Afonso I (112885), whose gold maravedis, copied from the gold of the Berber Almoravids, retained certain Arab features in design. Some base silver was also struck. Rights of coinage were, from the start, reserved to the kings, almost exclusively. Peter I (135767) reformed the coinage on the basis of the gold dobra of about 4.9 grams, with types copied from those of contemporary France: obverse, king enthroned; reverse, ornamental cross. There was a similarly imitative silver gros tournois (based on the weight standard of Tours, Fr.). Peter's successors developed his system. Copper was struck from the 15th century. From the 16th to the 18th century, gold was coined in quantity and in denominations of handsome size down to the half-escudo. In the 19th century the basic gold denomination was the crown. In the 20th century token denominations (in terms of centavos) have prevailed in various alloys, though silver was introduced in 1954 for the 10-escudo piece and for certain purely commemorative issues.