INNOVATIVE COINAGE CONCEPTS SESSION MDC San Francisco / March 2004 17/01/2004
INNOVATIVE COINAGE CONCEPTS:
FOR WHAT DOING? SEEN FROM A TECHNICAL POINT OF VIEW
hen the Product Development and Marketing Department of a Mint begin to start their brainstorming on possible new products, that “ have to be so appealing, attractive, W innovative and “jamais vu ”, it is well know that usually, the Production Department starts becoming headaches. Each technician in this room knows what I am talking about!
However, in this paper, I will try to illustrate through an non-exhaustive list what kind of innovations have been achieved in the last past years, and what were the difficulties faced, the limits that had been pushed out to create these innovations, and finally put on the market as “ innovative coinage concepts”.
In the classical numismatics field, circulation or collector coins are understood to be:
1-round 2-flat 3-light and small 4-in one piece 5-in a limited range of metals 6-only metallic 7-in a limited range of colours 8-in a limited range of finishes
What we can call the 8 classical rules.
However, as the number of products grove rapidly in the last 20 years, the Mints of the world have rapidly seen that there is a real challenge in introducing innovative numismatic products ( the so called Collectors’ Coins) in their classical product range, as it is a window on their company showing values like for instance:
-modernity -fashion spirit -technical know how or engineering capacity which are clearly aimed to be sales arguments and boosters for the turn-over.
Therefore, Marketing people and Technical people began to sit together and state that a collector coin can be more than a copy of a circulating coin, and that there is room for creative designs and innovative techniques.
Nowadays, although a coin remains a mean of payment by carrying a face value, it DOES NOT anymore have to follow the above mentioned 8 classical rules.
PASCAL RENCKER Page 1/14
INNOVATIVE COINAGE CONCEPTS SESSION MDC San Francisco / March 2004 17/01/2004
However, there are some difficulties ahead, for one who wants to get a rid of these specifications, and this is illustrated hereunder:
1- COINS DO NOT HAVE TO BE ROUND:
Example 1: Poland 2003 Rectangle Silver Coin “Famous Painters Series”
Example 2: Slovakia 2003 Square Gold and Palladium Coin “10th anniversary of the Republic”
Example 3: Slovakia 2001 Triangle Silver and Gold Coin “New Millenium”
Example 4: China 2002 Fan-shaped Gold Coin “Year of the Horse”
Example 5: The extreme: Nauru 2002 Europa-form Silver Coin “Euro introduction”
PASCAL RENCKER Page 2/14
INNOVATIVE COINAGE CONCEPTS SESSION MDC San Francisco / March 2004 17/01/2004
In the case of non-round coins, from the simple rectangle to the complex shape, the problems occurring are usually:
- blank-ring interval not regular : gives different pressures while striking and therefore early break of dies
- blank profile not adapted : edges not complete, some reliefs not completely struck. The main trouble appears in the corners, where metal has to be placed first in the early pressure stage, while the flanks come out in the end; requires a special profile of the blank. The more the corners are sharp, the more difficult it is to get a completely struck coin, even in multi-strike.
- Coin is struck with irregular rim: the rim’s width is varying because of geometrical unfitting between dies and ring ; needs devices for fine check of the slack between dies and ring and micrometric moving.
- Special shapes like the Nauru coin requires high precision electro-erosion process for ring and dies. Depending on the design, sometimes a strike-and-cut process can be used, but for adapted forms and very thin materials that can then be used in the form of polished prepared silver coils for instance.
2- COINS DO NOT HAVE TO BE FLAT:
Example 1: France 2001 Wave formed Gold and Silver “Ultimate Franc by Starck”
The main troubles we experienced at Monnaie de Paris for the wavy form of the Ultimate Franc are directly linked to the curvatures the coin design requires:
- Early break of the dies due to a very slight difference in the 3D complex form of the wave of the upper die compared to the lower one. This brought a squeezing point which concentrated the efforts leading to the break, always at the same point. The solution has been found in mounting the dies in the way which respects the natural flow of metal, in following the wave, and feeding the blank accordingly.
- The finish of the coin was irregular, and the more unacceptable that the coin had no further stage of treatment (lacquer or protective capsule). The blanks have therefore been prepared in a special way, with deep degreasing and etching, followed by glass balls process.
- Insculpation had to be done on the edges after striking, what means rolling an uneven 3D-form through the edge lettering machine with very poor relief. The coin refused to engage itself, and had a tendency to skid like a wheel. When this happened, the coin turned into a reject. Special holding material and feeder allowed finally a successful insculpation on a big scale.
PASCAL RENCKER Page 3/14
INNOVATIVE COINAGE CONCEPTS SESSION MDC San Francisco / March 2004 17/01/2004
- Uncomplete edge/ outer rim, on the side of the lower point of the wave. This was due to a lack of metal on the point where the blank had its last forming, leaving an edge slightly turned upwards. Here again, a special profile of the blank was found necessary.
Example 2: Congo 2002 Relief and hollow combined Silver Coin “Polaris”
Obverse
In this case, the originality is that the classical lettering in relief is combined with the hollow triangles, rather deep, the bigger ones being at places α,β,γ, and ξ .
- When finish of coin requested is proof, it becomes difficult to have the combination of both relief and hollow patterns. A special die polishing procedure is here certainly required, giving the mirror surface and saving the edges of the geometrical triangle forms. This can lead to others designs based on the same idea, even with deeper patterns in using a “piéfort” blank for instance.
Example 3: Hungary 2002 Hollow with screw compartment Base metal Coin “Message-Communication”
Coin closed, Reverse
- This interesting BU coin of 1000 Forint in CopperZinc is in two parts, the obverse being screwed to the reverse and creating a small compartment while closed. - The idea in itself is not new, as some prototypes appeared as soon as in the 19th century, but these coins were only single specimens. - The issue limit of this coin being as much as 15 000 units, the fabrication process needed to be automatized to keep the costs acceptable. - The question is then: how to mint without damaging the hollow, or how to hollow without destroying the engraving, even if not a proof surface.
PASCAL RENCKER Page 4/14
INNOVATIVE COINAGE CONCEPTS SESSION MDC San Francisco / March 2004 17/01/2004
3- COINS DO NOT HAVE TO BE LIGHT AND SMALL:
Example 1: Australia 2000 1 kg Silver Coin “Sydney Olympics”
Example 2: France 2003 1 kg Silver Coin “First anniversary of the Euro”
Example 3: China 2002 1 kg Silver and Gold Coin “Jubilee of Panda Series”
Example 4: Fiji Islands 2004 project of a 2 kg Silver Coin “Battle of Trafalgar”
In these 4 examples, the same basic problems were faced by the producers:
- How to design the 1 kg blank so that the result will be a Proof Coin? On these large blanks, around 100 / 110 mm diameter, the surface of the blank is so important that the rolling mills specific forms and stripes still appear under the tribo-finished upper layer: the outcome is then undulating, wavy uneven proof field, and unidirectional stripes, not compatible with the Proof appellation.
- To reduce these consequences, the blank usually goes through different phases of preparation, which are depending on the press used: in general, hardness should not be too low (which is not easy with a 999 silver), and the blank should not be polished, as it reinforces the defects, but experimented with an adapted brush-finish.
PASCAL RENCKER Page 5/14
INNOVATIVE COINAGE CONCEPTS SESSION MDC San Francisco / March 2004 17/01/2004
- The profile of the blank has to be adapted: here, no way to work on the rim, as there is no rim, but, depending on the Mints, a 45 ° angle on edge, or a rounded corner. And before this, the cut diameter should be significantly bigger than the finished blank diameter, to avoid the disturbing “fall” on the outer part of the profile, which creates then un-complete outside engravings on the struck coin.
- One should also avoid what we at Monnaie de Paris have experienced, which is the deformation of the original model : as the Europa coin was declined is several different coins in a complete range from 37 down to 22 mm, only one reference obverse model was created, in 90 mm diameter. Therefore, we had to enlarge this reference model, in order to use it for the reducing machine with a minimum coefficient of 2, what means a 200 diameter for the new model, which contained the inherent distorsions due to enlargement process.
- The australian coin has on the top of that to deal with the problem of pad printing on large/heavy pieces, and the chinese coin with the specific problem of the 2 golden cameos, not easy to carry out on such very big products, as gilding lines are ususally designed to process much smaller pieces.
- Of course, there is an actual trend for bigger sizes, but this market is a niche-market, and therefore the race “to be the biggest” is limited ; information about a giant 4 kg Silver coin does exist, but in this case, a very limited issue (200-400 pieces) would rather conduct to consider it as a medal process (with the same steps of operations) rather than a minting process.
4- COINS DO NOT HAVE TO BE IN ONE PIECE:
Example 1: Hungary 2000 Split Silver Coin
This is an example of the split coin family, where the 2 parts are equal and forming a half moon shape. Other examples of coins existed, in two or three parts, with broken separation line between the parts.
In this example, the 2 parts can be struck separately, as they have the same ring and form of dies. However, in the case of a broken line, some trials have given good results, where 2 or 3 parts of blanks were mint together in one striking process. But this requires exact shapes, positioning of the parts and edge preparation to avoid the “cold welding” of these parts in one block.
Example 2: Australia 2002 Trimetal Gold Silver Copper Coin “Commonwealth games”
PASCAL RENCKER Page 6/14
INNOVATIVE COINAGE CONCEPTS SESSION MDC San Francisco / March 2004 17/01/2004
This coin is a nice application of the tri-metallic solution, where copper is dared to be used with precious metals like gold and silver, for symbolic reasons. The big challenge in this case, is to: - avoid oxidation of the copper by using an adapted protection (finish/lacquer/ and /or capsule) - avoid chemical reactions between the copper outer ring and the silver inner ring, turning the interface reddish. - assure the good serration of the 3 parts together through one sole striking cycle.
Example 3: Australia 2003 Star shape insert Gold and Silver Coin “Jubilee of QE II”
This is a genuine example of a complex bimetal inner profile, where the star-shaped insert fits into its counterpart in the ring, using a specific profile obtained by blanking. The geometrical figures have to be very precise, giving the same slack on every point, and therefore requiring specific tooling for the blanking, which leads to higher fabrication costs.
Example 4: France 2003 and 2004 Complex shape inlay Silver and Gold Coin “The Sower”
The complex geometry of the centre part (solid inlay) is struck into the silver surrounding blank with mechanical grip. The inlay had to be defined carefully: the specific problems were linked to the feeding, the blank dimensions and the order of the operations:
- The first trials went wrong because of too weak material: the gold inlay was too ductile, and the overlap was visible. It had to be changed into the right alloy (finally Au 920 Ag 40 Cu 40) and the right hardness. - The positioning of the inlay was manually done and not repeatable, what conducts to small but visible differences between the coins. - The dimensions of the inlay were first too big, then too small, to be finally exactly designed for the fitting. The total trials covered an important part of rejects before the right inlay profile and the order of operations were defined.
Example 5: Isle of Man 2002 Moveable silver disc Coin “Currency Converter”
The coin is original because it bears a moveable disc, rotating around a central pin, fixed onto the bronze blank, giving the conversion from one currency to another.
PASCAL RENCKER Page 7/14
INNOVATIVE COINAGE CONCEPTS SESSION MDC San Francisco / March 2004 17/01/2004
- The crucial question is here: how to generate the pin? Should it be created during the striking operation or is it fixed afterwards? - How to mount the disc without blocking its rotation? Is there a way to automatize this or is it the work of jewellers, where each part has to be mounted manually?
Apart from the idea itself, this coin appears to be probably the first “articulated coin” in History. This could be a new direction in which new products could go.
5- COINS DO NOT HAVE TO BE IN A LIMITED RANGE OF METALS:
Example 1: Austria 2000 Titanium Silver Bimetallic Coin “Millenium” and “Transportation”
Example 2: Austria 2003 Niob-Silver Bimetallic Coin “700 year Hall city”
These two examples show clearly that there is still room for innovation, even in the choice of materials, out of the trilogy: Gold, Silver, and Platinum. Some years ago, we experienced in Europe a small market for Palladium Coins. But it vanished in the mid-90s.
Some trials had been made with rare metals like Rhodium, or Ruthenium, although the visual aspect was not always appealing, and the marketing arguments not easy to develop on the reasons of these choices.
But the choice of Titanium and Niob in these coins had here in both cases evident justification :
- Titanium is a metal linked to high performance equipment, in aviation or space industry, and therefore symbolic for technology and new millennium.
- Niob, a rather soft and ductile white material, is usually rather used as component in stainless steel for nuclear reactors, jets and missiles. Its specific colour varies from white to light blue when temperature increases.
These two coins have a nice looking, and a strong history to tell; this is not the same than an oxidized aluminium casino token for instance, which by the way can conduct to nice colours too, but is not valuable on the collector’s market. But specific problems do appear in these examples: - risks of chemical reactions between ring and heart, - hardness not adapted to match with silver ring, - difficulties in sourcing of the right alloy.
PASCAL RENCKER Page 8/14 INNOVATIVE COINAGE CONCEPTS SESSION MDC San Francisco / March 2004 17/01/2004
In addition, these materials need a specific treatment to appear respectively grey and light blue, and the producer has to guarantee that they will remain stable in aspect.
However, these trials launch new ideas : why not using materials with specific colour changes in the temperature range between -10° C and +40 ° C, for instance (human being conditions of life) ?
It might be recalled that in some other industries (carmakers, household equipments...) , were design plays an important role, some producers are already on the topic.
6- COINS DO NOT HAVE TO BE ONLY METALLIC:
Example 1: Poland 2002 Silver with Amber insert Coin “Fifa 2002 World Cup”
Example 2: Poland 2002 Silver with Ceramics Coin “Malbork Castle”
These are two interesting examples of using precious material that do not degrade the gold or silver coins, but on the contrary enhance their “jewel-like” look, despite of still being a coin.
However, this type of materials can not be struck, and need therefore to be fixed after the striking. In this field, most of the products use adapted glue. The exact fitting of the non-metallic insert into the hollow in the coin is the usual difficulty in these products.
Example 3: Cook Islands 2002 Gold Coin with tiny precious stones in acrylic box “The Crown Jewels”
This example is far more surprising, as it uses an acrylic capsule to hold micro –jewels, and capsule being the centre of a gold coin; This innovation has mainly to deal with the exact fitting between both components: the capsule is mounted after the striking of the ring, therefore the ring has to respect the exact foreseen inner diameter, to avoid being slack or too tight.
PASCAL RENCKER Page 9/14 INNOVATIVE COINAGE CONCEPTS SESSION MDC San Francisco / March 2004 17/01/2004
During the minting, something has to hold the ring on the inner side, to contain the efforts coming from the “pushing in” of the ring to the centre. It is impossible to blank the hole after the minting, as the proof quality does not permit it.
7- COINS DO NOT HAVE TO BE IN A LIMITED RANGE OF COLOURS:
Example 1: Tampography or “pad-printing” in general Liberia 2004 silver coins “Moments of freedom”
Tampography or “pad printing” appeared several years ago, and offered almost all kind of colours and patterns on collector’s coins. Mints around the world tried or adopted this technique and many coins are put on the market each year. However, even if tampography has its own difficulties, one can not really classify it as an “innovative coinage concept”, as the technique was very broadly diffused before, using all kind of supports (cardboard, plastics, metals, textiles etc…). We choose therefore to speak about others techniques used in the coin business:
Example 2: France 2002 Translucent enamels Silver Coins “Fairy Tales”
The translucent enamels were first introduced in 2002, as Monnaie de Paris was looking for an alternative to both tampography and classical enamels, keeping the high valuable aspect on one hand and lowering the costs on the other hand.
The originality of this feature is that the bottom of the coin, behind the enamels, is still visible, and therefore has a game to play, delivering its surface roughness or specific relief, under the enamel cover.
The result is a coin more lively than a simple “cloisonné technique” with opaque enamels or resins. The difficulty that occurred is that the final visual aspect of the coin is very difficult to predict, and it needs several prototypes to check that the visual impression which is finally given is the right one.
PASCAL RENCKER Page 10/14 INNOVATIVE COINAGE CONCEPTS SESSION MDC San Francisco / March 2004 17/01/2004
Also, as the process requires a heating, there are two more dangers: oxidization of the silver, and slight changes in the final colours.
Example 3: Canada 2004 Total Hologram Gold Coin “Year of the Monkey”
Here comes the “holograms family”: holograms have been introduced several years ago, usually coming from other applications in the industry: smart cards, banknotes, security films, etc
In this example of coin, the complete surface of the obverse is covered by the hologram, and no struck engraving appears. This kind of hologram is however more easy to master than when you have to deal with certain zones of the obverse which are struck, and which create problems during the hologram transfer process;
Example 4: Laos 2004 Holographic background Silver Coin “Black Gibbon endangered Wildlife”
The particularity of this hologram is that it is interrupted by the central engraving (the Gibbon), which is a nice design choice but a pain for the process: As the holographic transfer is necessarily done in a second step, it means that the central Gibbon engraving plays the role of a trouble-shooter. Being pro-eminent and not flat, it creates difficult conditions for the application of the hologram with precise location, and with an acceptable die life. In that case, production can be a tough thing to achieve.
Example 5: Congo 2003 Incrusted partial hologram “Victoria Falls”
Here it is the contrary: the minted rock walls outside on left and right and the leaves upside delimit the waterfalls and the sky, which is rendered by the 2 D Hologram, which had to be inserted properly and in a smooth way into this 3 D engraving surrounding:
- a tendency of un-complete hologram can been seen near the leaves and down, around the year of mintage. - the insertion of the hologram is here even more complicated, as scheme cut and location need dramatic precision.
PASCAL RENCKER Page 11/14 INNOVATIVE COINAGE CONCEPTS SESSION MDC San Francisco / March 2004 17/01/2004
Example 6: Australia 2004 Dynamic Hologram on Aluminium Bronze “Five Kangaroos”
This nice and last example just came out: the hologram is posed on the reverse of an aluminium bronze coin (non precious alloy and in large quantities) and follows a new process. The Mint collaborated with a specialized company to work out a new method of “replica micro moulding”, using a new type of elastomer stamp to transfer the micro patterns it bears directly on the coin through smooth squeezing of a thin resin layer applied on the reverse of the coin.
Here, the challenge is : - to master the material (elastomer and resin layer), as well as - to master the engraving through electron beam on the elastomer ( which is in fact a kind of “service die” ) - to control the micro patterns visual result (iridescent and moving when tilting), piece after piece, as the image, has to last long enough to amortize the tool.
8- COINS DO NOT HAVE TO BE IN A LIMITED RANGE OF FINISH :
Example 1: Finland 2003 Diamond Proof quality Year-set
For years, Year-sets have been presented in three different qualities (circulating, brilliant uncirculated, and proof).
The Mint here tried to open this limited range, and proposed a new “Diamond Proof” quality, (patented);
Each service die is covered with an amorphe diamond layer, giving through the minting process an exemplar and specific shiny finish to the coins.
Even if this evolution is probably not going to be generalized, it shows that new results can be achieved even in re-thinking old processes.
PASCAL RENCKER Page 12/14 INNOVATIVE COINAGE CONCEPTS SESSION MDC San Francisco / March 2004 17/01/2004
Example 2: Zambia 2004 Diamond Cut Silver coin “Calendar 2004”
This heptagonal shaped coin is treated like the jewellers, “Diamond Cut”, giving a new appearance to the surface of the coin, the texture becoming a bit “grainy”, but with regular and fine patterns.
The difficulty is that the coin is rather big, and that the finish must be very reproducible, without defects, or visible deterioration of the texture due to early tool wear.
Example 3: Isle of Man 2003 3-colors finish Silver Coin “Jubilee of QE II”
The originality of this coin is that it combines 3 different finish of solid silver : the inner part is a regular silver colour, the intermediate part is a bright yellow gilt silver, and the outer ring is a controlled oxidized “dark” silver. To achieve this, in theory 2 techniques can be used :
- operate 3 different surface treatments on a one piece struck coin, or
- minting 3 separate parts together, which have been prepared before with the right surface- treatement.
In each case, specific difficulties do exist, but from our point of view, the second one is more reliable and generating much less rejects.
Example 4: Canada 2002 Partially Oxidized Gold Coin “Alberta Oil Boom”
Here is a example of what can be done when using specific properties of the metals : even materials like gold can turn by the presence of unexpected chemicals into coloured stains or spots; different colours can be generated, but the whole thing is to master their size and form.
In this case, the black colour has been produced by using a specific oxidization of the gold alloy, but within a mastered pattern, which has to be fully reproducible. An additional difficulty is that the process has not only to be precise, but also very clean, to avoid undesirable stains located outside of the foreseen pattern. On the contrary of a pad-printing for instance, these stains will not be removed.
PASCAL RENCKER Page 13/14 INNOVATIVE COINAGE CONCEPTS SESSION MDC San Francisco / March 2004 17/01/2004
CONCLUSION:
The selected examples above show only some of the difficulties faced by mints’ technicians in the creation and production of innovative coinage concepts, but as my colleague Gilles said, innovation creates success, and success in innovation creates further success. Most of the examples shown in this paper are products which finished “sold out”.
Therefore, my conclusion would be : as long as a Mint’s technical department is able to provide the marketing department with solutions to the new concepts, one can say that “innovative coinage” definitely play an important role in a Mint’s capability to attract (and keep) its customers.
I would like to thank the concerned Mints for their courtesy concerning the use of their products as selected examples.
I thank you for your attention;
Pascal RENCKER Deputy Director of the Pessac Minting Facility
PASCAL RENCKER Page 14/14