In order to experience the many pleasures that coins have to offer, it is necessary to know how they are made. When the collector understands this he may then be in a position to appreciate more fully the beauty of the Ancient Greek coins or the reason why some modern coins are found with flaws in them.Basically, a coin or medal may be made by one of two processes. It can either be made by casting in a mould or struck between two pieces of metal bearing an impression. The first method is probably the simplest and least expensive but it is impossible to obtain a really clear impression by casting, particularly if the details are finely drawn.
It would, therefore, be necessary to clean over the whole of the design on each coin to render it reasonably clear. Obviously, this process would take far too long when coins are produced in huge quantities and because of this all coins and medals are nowadays produced by striking. The date of the invention of coinage has always been a matter for conjecture. Most authorities are now inclined to place this important event roughly between 640 and 630 b.c. The first coins were bean-shaped blobs of metal and were impressed on one side with a lion’s head design whilst the other had four rectangular punch marks.
Possibly only one die would have been needed to produce this coin. The die or piece of metal bearing the engraving of the lion’s head would have been necessary—perhaps it was engraved on an anvil—but the punch marks on the other side could have been made by either one or two punches. The blob of metal would have been placed on the anvil, the punch placed on top and then hit smartly with a ham¬mer. Naturally, the metal would expand into the design and flow sideways into an irregular shape. The most difficult part of the whole operation was the production of the die bearing the design.
This, being made of iron, was engraved with the design and naturally, the artist would be working the lion motif in reverse. The artist would have been called upon to produce more than one die, not only because the design would eventually become worn but because the top of the die would suffer damage due to the frequent blows received from the hammer. The constant call for new dies would inevitably produce slight variations in the design, no matter how careful the engraver might be. At a later stage, we shall see how modem coining methods have overcome this difficulty. The practice of engraving dies by hand continued for many centuries. Very early in the history of coinage two dies, one for each side of the coin, began to be used. This increased the amount of work and the difficulties for the artist. He found that he was required to produce more examples of the die that was struck by the hammer than of that of the die that Was not.
By Norman times in England an improved method of making the dies had come into use. Instead of the whole of the design being engraved, it was punched into the die by a number of differently shaped punches. Those parts of the design such as portions of the head, etc. that could not be made by using these were made by gouging directly out of the die.Various types of dies are known to have been used. The conventional types were cast cylinders of iron, some eight inches long, with one end filed smooth to take the design. The lower end of the trussel ended in a spike for driving into a block of wood. At this period the blanks that were placed between the dies were flat so that they would not roll off. At an early period when this was not the case some of the lower dies were concave. It was inevitable that on occasions the pile was not placed accurately on the blank, so that part of the design was missing on the finished coin.
In order to prevent this and ensure that the dies were always in perfect alignment, some dies were hinged or were given pegs and sockets which fitted into one another. The methods used to produce the blanks ready for coining varied considerably from age to age. During Norman times the ore was probably heated in pots over charcoal fires, the impurities skimmed off and the molten silver cast into thin ribbons. When cool, these were beaten into the required thickness and cut into disks with a pair of shears.
Sometimes one end of the shears was attached to the work bench to enable the worker to put greater pressure on the upper lever. This was found to be necessary since by the thirteenth-century minting techniques had changed considerably. In England, instead of the metal being cast in ribbons, it was poured into sand moulds and cast into rectangular rods roughly equal to the area of the coin. These ingots were then cut into thin slices and hammered to an approximate circle. Following this operation the blanks were weighed. Any that were found to be below the tolerance allowed were discarded and went back to the melting pot. Those that were overweight were trimmed and filed to the required weight and went to the moneyer to be cleaned and then to be struck with the dies. Plate I is taken from a French print and shows a typical mint workshop during the sixteenth century.
During the Renaissance machinery had begun to be used in the manufacture of coins. Leonardo da Vinci (1452-1519) produced drawings of a machine for cutting the blanks and accompanied the drawings with the following far-sighted notes: No coins can be considered as good which have not the rim perfect, and in order to ensure the rim being per¬fect it is necessary first that the coins should be absolutely round.
In order to make this so, it is necessary first to make the coin perfect in weight, breadth, and thickness; therefore you must first have many plates made of this uniform breadth and thickness drawn through the same press, and these should remain in the form of strips, and from these strips you should stamp out the round coins after the manner in which sieves are made for chestnuts and these coins are then stamped in the way described above.”
Bramante, a contemporary of da Vinci, devised a type of screw press for striking coins. Somewhat later, Benvenuto Cellini (1500-71) used machines similar to those invented by da Vinci and Bramante when he was com¬missioned to strike medals and coins for Pope Paul III. On his accession in 1547, Henry II of France inquired into reports that a workman in Augsburg had invented a machine which would produce perfectly rounded edges on coins. Aubin Olivier, acting on behalf of the king, purchased the invention for 3,000 ecus—a not inconsiderable sum and returned with it to Paris, where it was installed in a new building at the bottom of the palace gardens.
Several machines were involved, including rolling mills for producing the lengths of metal and draw benches for making the bars of the correct thickness. Blank casting presses and coining machines were also purchased.
During the reign of Elizabeth I of England the Tower Mint, as it was then called, underwent a brief attempt at mechanisation. The Queen’s Council installed Eloye Mestrelle, a former employee of the Paris Mint, in a house at a salary of £25 per annum with instructions to produce coins on presses he apparently brought with him from Paris. The presses for cutting blanks and striking coins were of the new screw type and were worked by horse and water power.
Although the new coins were much superior to the existing specimens that were struck by hand, the Mint employees feared for their jobs and raised many objections. The Warden of the Mint conducted an investigation which showed that while Mestrelle’s technique produced better coins it was much slower than the old method. Mestrelle was sacked from the Mint and was subsequently hanged for counterfeiting in 1578.
Further advances were made in the mechanisation of the Tower Mint during the reign of Charles I. Nicholas Briot was, like his predecessor Mestrelle, formerly employed by the Paris Mint. He came to London in 1625 and a few years later was commissioned to design portraits for coins and medals.
By using his supreme skill as an engraver and a modified version of the screw press, together with a collar to prevent spreading of the metal when struck, Briot was able to produce some of the most attractive coins in the English coinage. Unfortunately, he was not able to keep pace with the requirements of the Mint and the old hand-coining methods continued.
The seventeenth century saw the final relinquishing of the old hand-made or hammered coins.
Hammered coins were prohibited in French mints in 1645. In England, a great step forward was made by another Frenchman, Pierre Blondeau, when he devised a means of marking the edge of the coin either with graining or an inscription. It was thus possible finally to defeat those people who had made a profitable living by clipping the edges of the coins, passing them on, melting the residue and selling it as bullion.
During the seventeenth century various other forms of presses were used, some of which rolled the design on the blank instead of striking it.By the middle of the seventeenth century, die cutting techniques had advanced considerably. In medieval times it had been impossible to make all the designs and portraits on the coins exactly alike. A great number of dies were required for a large issue and by various processes, this was now possible. The portrait on the obverse or the central design on the reverse was engraved incuse into the smooth end of a cylindrical piece of steel. The individual letters and other parts of the design were similarly prepared; the resultant tools are known as matrices. From each matrix, an individual puncheon was produced by “striking” it in one of the coining presses. A die was then made by striking the puncheons into its surface.
When the task was completed the die was hardened prior to striking the coins. With various modifications, this process is much the same as that used today.