The last execution for forgery took place in 1830 and Victorian forgers were punished by transportation, imprisonment and hard labour. The punishment for counterfeiting today is several years’ imprisonment.

Have you ever been guilty of passing fake coins?

A forged Charles I half-crown. The corroded base metal core can clearly be seen through the thin silver plating.

Your answer will hopefully be, “no, of course not!”, but would you be able to spot one if you saw one?

According to the Royal Mint, just over 2.5% of the £1 coins circulating in 2015 were counterfeit, so how many of us have unwittingly broken the law by handling fake money? But far from being a modern problem, you may be surprised to learn that counterfeit coins have been causing headaches for the authorities for thousands of years – for as long as we have been using money, in fact.

Occasionally, metal detectorists who unearth coins and report them to the Portable Antiquities Scheme in Wales (PAS Cymru), are told that what they have found is not what it seems to be – it is in fact a fake. In 2015, out of 679 coins reported, seven were judged by experts at Amgueddfa Cymru-National Museum Wales to be contemporary counterfeits. Many more were described as ‘irregular’ and therefore also produced under suspicious circumstances.

One of the fakes was a Charles I half crown, discovered by Mr Nick Mensikov at Miskin, Rhondda Cynon Taf. A half crown is a silver coin, but Mr Mensikov’s example gave itself away as a fake because corrosion revealed it to have only a thin coating of silver over a copper alloy core. In ‘mint’ condition it would have looked sound enough to the untrained eye, but its real value would have been well below the two shillings and sixpence (or one-eighth of a pound) that the half crown represented.

Twelve fake coins from the reign of Charles I found in Wales have been reported to PAS Cymru since 2009, far outweighing those of any other monarch, but the great majority are much older than this and date from the period of Roman occupation, from the first to the early fifth century AD.

Who made counterfeits, and why?

Counterfeit coins were made for several reasons in the past. Sometimes, when supplies of the smaller denomination coins were inadequate, unofficial production took place to make up the shortfall. In Roman Britain this happened to such an extent that at some periods there may have been as many fake coins in circulation as real ones. After Claudius’s invasion in AD 43 the Roman army itself may have been responsible for much of this ‘irregular’ coinage, which was sometimes tolerated by governments as being something of a necessary evil.

In other cases, people forged coins purely and simply for monetary gain. Of course, this was not an easy process. It required access to supplies of metals, a furnace or crucible, and various other bits and pieces of equipment, including dies or moulds on which had been engraved a passable copy of the coin to be reproduced. This meant that forgery operations generally involved more than one person, as well as some initial financial outlay, and so they were not the last resort of a poor man or woman with no other way of getting cash.

Some ‘coiners’, as forgers were sometimes called, were already wealthy individuals. In 1603 a coining operation was uncovered at Duncannon Fort in Ireland. Moulds, pieces of brass, crucibles, as well as chemicals and charcoal, were discovered in the desk of the fort’s commander, Sir John Brockett. Sir John had been producing counterfeit English and Spanish coins, for which he was put on trial for treason.

Some forgeries were never intended for use as cash, however. As early as the sixteenth century antiquaries and collectors began to be interested in old coins, and consequently some unscrupulous individuals went into business supplying fakes to tempt the unsuspecting or naïve. In early Victorian London, one Edward Emery was responsible for passing a possible 5-700 fake medieval and Tudor coins onto the collectors’ market. Roman coins were also highly collectable, and a modern era replica of one was found by a Mr Rogers in Usk in 2007. Made of a white base metal alloy designed to look like silver, was it thrown away in disgust by its owner when he realised what he had bought?

How were counterfeit coins made?

There were two main methods of producing fake coins – striking them from stolen or forged dies, or casting them in moulds. A coining operation in Ireland in 1601 used metal and chalk dies to strike the coins, which were made of an alloy which included enough tin to create the necessary silver colour, although the coins, of course, contained no precious metal. This was obviously a noisy activity and so coining dens were often located either in busy areas such as town centres where the noise and activity would be masked by the hustle and bustle of the streets, or in out-of-the-way places where people were unlikely to go. The latter option was chosen by the Roman forgers at work in the lead mine at Draethen, near Caerphilly. Discovered here were coins, the ‘flans’, or blanks, from which the false coins were struck, as well as the metal rods from which the flans were cut. These items were found around a hearth, and we can only guess at the hot, unpleasant and dangerous atmosphere that this subterranean forging operation would have created.

Casting was a different process, but it still required access to a powerful heat source as molten metal was required. An impression of both sides of a genuine coin was made in clay, wax or ashes. The hardened moulds were then fixed together and filled with molten metal alloy. Some cast coins are given away by the tell-tale remains of the channel through which the metal was poured and which wasn’t properly broken off or filed down. There has been plenty of evidence for this forging method from Roman London, consisting of both the cast coins themselves (often in a silvery-looking alloy of bronze and tin) as well as hundreds of moulds.

The appearance of precious metal necessary to pass off a fake coin was not only achieved by cunning uses of alloys (some of which included arsenic for a whitening effect!). Some coins – like the Charles I half-crown mentioned earlier – were made from base metals which were then plated with a thin coating of silver or gold to achieve the desired effect. Medieval forgeries often used a technique called fire gilding. A base metal blank was rubbed with a mixture of gold and mercury which was then heated. The mercury was evaporated and the gold was bonded to the surface. The coin could then be struck between the dies.

This process obviously required some technical skill, and there is evidence that forgers were experimenting with methods that would later be used for more legitimate purposes. A counterfeit coin of William III (1689–1702) was found to have been made by an early example of the Sheffield plating technique. A copper plate was rolled or hammered between two thin sheets of silver from which blank coins were then cut out. The edges were covered with a copper and silver alloy and the blanks were then struck with official dies smuggled out of the London mint.

The gold and silver necessary for the plating were sourced by clipping real coins (an offence in itself) as well as melting down pieces of plate or other coins.

Punishments

The severity of the punishments for counterfeiting have reflected both the seriousness of the crime but also the difficulty of detecting those responsible. Like many penalties of the pre-modern era, they were physical in nature. In ancient Rome it was a capital offence, equated with treason, and could be punished by banishment or slavery if you were lucky, or crucifixion if you weren’t. In the early 4th century, Emperor Constantine – who is more famous for making Christianity the official religion of the Roman Empire – introduced burning for forgers.

In 10th-century England, under King Athelstan (927–939), the forger would lose a hand, but one of his Norman successors, Henry I (1100–1135), went one better. Suspecting his official mint workers of producing irregular coinage on the side and unhappy with the standard of the regular issues, he summoned them to a Christmas gathering at Winchester where he took the right hand and both testicles from each of them.

Under Edward I and later kings, death by hanging was the usual punishment for men, with burning and strangulation reserved for women. Three unfortunate 16th century Edinburgh women suffered this appalling punishment, while in 1560 Robert Jacke, a Dundee merchant, was hanged and quartered merely for importing forgeries. Nineteen executions for counterfeiting took place in 1697 when Sir Isaac Newton was Warden of the Royal Mint.