Author Topic: Polygonal coins have many sides and many facets  (Read 30370 times)

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Offline <k>

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Polygonal coins have many sides and many facets
« on: May 21, 2011, 06:48:24 PM »
Polygonal means “many-sided”, but in numismatics the term “side” is used ambiguously in English. In England we have the saying, “There are two sides to every coin”.  A coin is being used as a metaphor here, but it does indeed have two sides: obverse and reverse. But in that case, what would a seven-sided coin look like?

Other languages are more logical than English, and they distinguish a “side” (obverse/reverse) from an “edge” or an “angle”. If you say a coin has seven edges, that makes an English speaker literally look at the coin from a different point of view. If you count, you will find that a seven-sided (or heptagonal) coin does indeed also have seven edges.

So in this topic, when I refer to “sides”, I do not mean obverse and reverse.

Offline <k>

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Re: Polygonal coins have many sides and many facets
« Reply #1 on: May 21, 2011, 06:49:43 PM »
My first question is, when was the first polygonal coin produced? I don't know, but I’m sure some of the members will have some clues. I imagine that we will be excluding hammered coins: they do not usually come in perfect classical geometric shapes. Or was there sometimes an intention to produce a polygonal hammered coin?

Next, you will ask, what do I mean by a coin? I am interested in the following categories:

1] Circulation coins.
2] Non-circulating legal tender coins.
3] Fantasies, which look like coins and may have a denomination, but which have no legal status.
4] Tokens: those which serve(d) as money, and those which do not or did not.

Categories 3] and 4] may overlap, but I don’t really want to discuss terminology too much; it’s more interesting to look at examples of numismatic polygons than to argue about categories.

I am excluding all banknotes, bills and postal orders. I am also excluding irregular shapes, such as the guitar-shaped or map-shaped "coins" that have been produced by some countries. Nor am I interested in coins that are actually circular but have a polygonal inner rim, such as the French 2 franc coins dated 1979 and later. Perhaps they deserve a topic of their own, though.

« Last Edit: July 23, 2012, 12:13:54 AM by <k> »

Offline <k>

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Re: Polygonal coins have many sides and many facets
« Reply #2 on: May 21, 2011, 06:50:30 PM »
When I talk about polygonal items, I am also including scalloped coins and so-called “Spanish flower” coins. Scalloped coins come with varying numbers of “scallops”, if that makes sense, but I don’t propose to differentiate between them. The Spanish flower shape originated in Spain in the 1990s but has been adopted by the Euro Zone, New Zealand and Azerbaijan. It is best described as circular, but with side notches at regular intervals along the edge.







« Last Edit: November 21, 2012, 08:12:42 PM by <k> »

Offline <k>

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Re: Polygonal coins have many sides and many facets
« Reply #3 on: May 21, 2011, 06:51:38 PM »
My second question is, out of these numismatic categories, which is or was the object that was produced with the most sides? Or to put it another way, what is the greatest number of sides to be found on any known numismatic item, as covered by my stated categories?

My third question is, can you date the first appearance of a numismatic item with a specific number of sides? Is it possible, for instance, to date the first appearance of a triangular numismatic item? In some cases this will not be difficult: the UK produced the first heptagonal coin, the fifty pence piece, in the late 1960s. The first fifty pence coins were dated 1969.

Offline <k>

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Re: Polygonal coins have many sides and many facets
« Reply #4 on: May 21, 2011, 06:52:18 PM »
My next question is: why were polygonal numismatic items first created? Three reasons stand out:

1] They were a challenge to man’s ingenuity and creativity.
2] Human beings love novelty.
3] Different shapes, in addition to size and colour, help to distinguish the coins of a series.

Are there any other reasons?

Offline <k>

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Re: Polygonal coins have many sides and many facets
« Reply #5 on: May 21, 2011, 06:53:03 PM »
Now we come to matters of practicality. How easy or difficult is it to produce a polygonal numismatic item? Is it more costly than producing standard circular ones?

Nowadays we have to consider vending machines, of course. A coin will only be accepted by a vending machine if it has constant diameter, or, in plain English, if it rolls. I do remember our member Tony Clayton trying to explain aspects of this in another topic. He struggled to explain it in a way that the other members could understand. Whether that was because the subtleties of such subjects are difficult to express in language, or because the concept he was trying to express was quite simply beyond me, or both, I simply don’t know.  In any case, this means that some polygons, such as triangles, squares and rectangles, cannot be used in vending machines. But does that mean that every other polygonal coin, from pentagons upwards, could in theory be used in a vending machine if properly minted?

Are there any more technical subtleties? I notice that a heptagon can be used in vending machines, because we have heptagonal 50 pence and 20 pence coins in the UK. However, the official name for them is “equilateral curve heptagons”. If their edges were not curved, would vending machines still be able to accept them? I don’t know the answer to that one.

Offline <k>

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Re: Polygonal coins have many sides and many facets
« Reply #6 on: May 21, 2011, 06:54:12 PM »
As for trends, some countries that used to use polygonal coins have recently stopped doing so. One example is the East Caribbean States (a currency union, not a country, of course). Another is Fiji: that country has replaced a twelve-sided 50 cent coin with a circular coin. The new 50 cent coin has a polygonal inner rim, so at a glance it still looks multi-sided, but it is not.  Is this because it is more costly or difficult for a vending machine to accept polygonal coins? I would imagine that vending machines are very hi-tech now and should have no problem with this, so long as the polygonal coins conform to standards by having a constant diameter.

In the case of the East Caribbean States, the square 2 cents coin with rounded edges was replaced by a circular coin, and a scalloped 5 cents coin was replaced by a circular coin with a polygonal inner rim. The square coin would not have been accepted by a machine. As for the scalloped coin, I am not sure, but I suspect not.





« Last Edit: May 07, 2012, 11:08:11 PM by coffeetime »

Offline <k>

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Re: Polygonal coins have many sides and many facets
« Reply #7 on: May 21, 2011, 06:55:11 PM »
Trends may occur for practical reasons or for reasons of fashion. Britain released its first heptagonal coins (the 50 pence piece) in 1969, and throughout the 1970s and 1980s various other countries also issued heptagonal coins: Mexico, Barbados and the Gambia, to name just three. I may be wrong, but I suspect that it is only British mints – the Royal Mint, the Pobjoy Mint – that have instigated heptagonal coins. However, other mints, such as the Royal Canadian Mint have sometimes taken over their production if they have won the contract.



« Last Edit: November 15, 2012, 08:34:28 PM by <k> »

Offline <k>

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Re: Polygonal coins have many sides and many facets
« Reply #8 on: May 21, 2011, 06:56:15 PM »
From the 1990s, the trend for heptagonal coins seemed to die away, and bimetallic coins became the new fashion. The 1990s also saw another rising trend: coins with an inner polygonal rim – South Africa springs to mind – but these are outside the scope of this topic. Maybe polygonal coins will become extinct in the next few years, but I would be sad to see them go: the 20 pence and 50 pence coins are among my favourites here in England, and they seem to be reasonably popular with the general public too.

Offline <k>

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Re: Polygonal coins have many sides and many facets
« Reply #9 on: May 21, 2011, 06:56:40 PM »
You would imagine that edge inscriptions would be suited only to circular coins, but the Pobjoy Mint (UK) minted some heptagonal coins with an edge inscription, as a gimmick or novelty. These were 50 pence coins, produced for the Isle of Man, but I can’t find any illustrations of the edges. The circulation UK 20p coins are also unusual, in that their surface is countersunk. Some coins have holes in them, but has anyone ever seen a polygonal coin with a hole in it? I can’t think of one.





Some countries have produced bimetallic polygonal coins. Cape Verde and Croatia are two such countries.






« Last Edit: November 12, 2012, 06:27:32 PM by <k> »

Offline <k>

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Re: Polygonal coins have many sides and many facets
« Reply #10 on: May 21, 2011, 06:58:33 PM »
The Cook Islands issued this triangular coin, but did it ever circulate?


 
« Last Edit: September 05, 2013, 08:06:34 PM by <k> »

Offline <k>

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Re: Polygonal coins have many sides and many facets
« Reply #11 on: May 21, 2011, 07:02:14 PM »
Square and rectangular coins (though with rounded corners) are reasonably common, but not all of them circulate.









« Last Edit: May 07, 2012, 11:13:34 PM by coffeetime »

Offline <k>

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Re: Polygonal coins have many sides and many facets
« Reply #12 on: May 21, 2011, 07:06:04 PM »
How many pentagonal coins do you know of? I suspect these are mainly collector coins and not intended for circulation.

« Last Edit: May 07, 2012, 11:14:16 PM by coffeetime »

Offline <k>

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Re: Polygonal coins have many sides and many facets
« Reply #13 on: May 21, 2011, 07:07:44 PM »
This Egyptian 2 piastre coin of 1944 is one of my favourite hexagonal coins.

« Last Edit: May 07, 2012, 11:14:40 PM by coffeetime »

Offline <k>

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Re: Polygonal coins have many sides and many facets
« Reply #14 on: May 21, 2011, 07:10:16 PM »
My birth country, the UK, invented the first heptagonal coin and exported the concept to other countries. Here is one from Botswana.

« Last Edit: May 07, 2012, 11:18:31 PM by coffeetime »