Sicilian minting "errors" explained.

[Deinomenid]

I just read an excellent article in the 2023 Koinon which summarises far more intelligibly some of the  key misconceptions on minting "problems" there.  Some  of it has been explained before, but not as clearly and there are  often  comments today  on  issues  like so-called sprues or gaps in coins, or what appear to be forgeries based on a second coin imprints on a flan.

(The coins are mine, but the photos of the clay models are taken from the article  -if that's wrong I will delete them and model my own. ) 

There are at least two excellent articles on this, both free in the Numismatic Chronicle, one from Hill back in 1922 and another,  more amusing but a good read from 1963 by Sellwood (of Parthian coinage fame) where he figuratively turned himself  into Greek  smelting specialist/engraver/minter. Indeed his obituary says that the workshops of his college, Kingston Polytechnic -

"became a branch of the mint of ancient Athens where David applied practical methods to answer the question of ‘not what was produced, but how much was produced’. Re-establishing the technology and metallurgy of antiquity, he made dies and struck coins to the extinction of the dies.... "

 

There are 3 key minting points explained  in the article. The first is sprues, which are not sprues at all, but the product of an unusual flan technique whereby the "flan" was a sphere, comprised of 2 pieces with a thick line around the equator. Below left.

 

When hit by a hammer at the intended this  produces above right. Image from the Numismatic Chronicle. And below, on my coin.

 

 

What I hadn't understood was that if those halves of the sphere are aligned but the sphere is placed at the wrong angle then they can produce this gap, which has vexed me  on a number of my coins. Five o'clock on the front hooves.

 

The article's author, William Daehn, demonstrates it as follows. I  know it's clay not silver, but...

 

And the last one, the one that most often gets called out as a poor forgery, but which perplexed me as the coins  I have seem fine, is a raised or stepped secondary flan. Sellwood had explained  it, but without the visualisation offered in Koinon, I had been flummoxed.

This stepped circle issue -

 

- from say 8 o'clock around to 4 clockwise. In case of any confusion this is my coin and/but the author of the article also uses it as his example. I'm not taking someone else's coin and claiming as my own.

 

The Koinon article demonstrated how this came about -

 

I just thought it was fascinating. None of it is my own work, It's all Hill, Sellwood and Daehn, and if  it's  in any way poor form to show  the latter's clay models I will remove them and make my own.  I only hope that as he used a coin I now own as a main example there might be some leeway!

These 3 issues come  up so often  in Sicilian coinage though that it is a pleasure to have  it more fully demystified.

Edited March 27 by Deinomenid
Typo.

[Phil Anthos]

Hmmm...

Fascinating and clever research. But why was it done this way. Is there a benefit produced by this seemingly convoluted production method?

curiously,                                    ~ Peter 

Edited March 27 by Phil Anthos

[Deinomenid]

Apparently it's a highly effective way of maintaining the heat in the flan-to-be. Making  it more workable and giving slightly more  time to manipulate it. Hill said similar and adds that it  didn't exactly catch on elsewhere!

The fact that a globe of metal retains heat longer than a disk may explain the fact that the blanks were made of a shape that would seem to place so much
strain on the dies, instead of something more -like the shape of the finished coin. The latter method was certainly employed by most other parts of the Greek
world. The lentoid shape of the blanks of the early electrum of Asia Minor, for instance, has hardly been altered under the pressure of the dies.

Other areas had  unusual techniques too - incuse in Southern  Italy for example -  but not for as long.

[Phil Anthos]

Heat retention, that makes sense. Thank you.

~ Peter 

[Ryro]

Very interesting and illuminating! Thanks for sharing @Deinomenid

One of my favorite ancients is a good example of this practice:

Sicily, under the tyrant Gelon Silver tetradrachm (16.91 gr, 25 mm)

Obv: Slow quadriga being driven r. by male charioteer, Nike above crowning horses

Rev: Head of Artemis-Arethusa right, 4 dolphins around legend, ΣVRAKOΣI-ON

Popular type. Boeh-353, SNG-113 Toned VF, obverse somewhat grainy. Purchased from Bill Rosenblum March 2022

[Romismatist]

Fascinating - thanks for sharing, I had no idea that this was how these coins were struck! Now at least I'm a little bit smarter...

[traveler]

Fascinating. Could the coin below also be an example of a "raised or stepped secondary flan"? Referring to the 9h position.

[Hrefn]

Posts like this are an ornament to Numis Forums.  Kudos.  

[JAZ Numismatics]

I'm guessing an addirional benefit to the balled-flan technique is that it would help the metal flow completely into the highest points of the devices, which are in the middle of the dies. Sicilian silver is frequently worn from circulatoon, but rarely do you find flat strikes.

Edited March 28 by JAZ Numismatics

[Bonshaw]

18 hours ago, Deinomenid said:

Apparently it's a highly effective way of maintaining the heat in the flan-to-be. Making  it more workable and giving slightly more  time to manipulate it. Hill said similar and adds that it  didn't exactly catch on elsewhere!

The fact that a globe of metal retains heat longer than a disk may explain the fact that the blanks were made of a shape that would seem to place so much
strain on the dies, instead of something more -like the shape of the finished coin. The latter method was certainly employed by most other parts of the Greek
world. The lentoid shape of the blanks of the early electrum of Asia Minor, for instance, has hardly been altered under the pressure of the dies.

Other areas had  unusual techniques too - incuse in Southern  Italy for example -  but not for as long.

I'm keenly interested in numismatic metallurgy, but am far from an expert, so please take this question in that spirit.

Why does heat retention in a flan matter? I assume that this is because it cools down slowly after an annealing step before the strike?

Am I correct that it is not because the flan needs to stay hot during the strike? Metals like silver are FCC (face-centered-cubic) structures, without a ductile-to-brittle transition. Their ductility is not improved (much) by heating them. I presume that these ancient flans were actually struck at room temperature. This is different from BCC (body-centered-cubic) metals like some steels. Those really want to be heated up before working. But silver, copper, and gold are all FCC. (I don't know about bronze alloys).

Edited March 28 by Bonshaw

[Deinomenid]

With the understanding I'm no expert,  just a couple of things.

Hill seemed to vacillate a bit on the purpose of the sphere, and also was made to say in Koinon as follows - As Hill surmised, a globe of metal retains heat longer than a flatter disk, thus making it easier to achieve a well-struck coin. Sellwood though WAS a metallurgist and described all sorts of different heat combinations. He repeats  the value of  retaining some heat to make a less stressful strike but also says a sphere is valuable  because there  is much less  surface area subject to oxidation. He also was a little concerned at numismatists  opining  on the subject -

So fanciful were some of the ideas about coins held by the early antiquarians, and so far at odds with common sense and ascertained historical fact, that it is little wonder that students of other disciplines still have no time for the opinions and theories of numismatists.

So with that warning, his main  interest was  in making sure the "flan" was sufficiently soft to allow easy hammering, for mass production, with a side order of lower oxidation. He was getting good results with one or two strikes, and some literature at the  time was claiming a dozen were needed. He was also particularly concerned about heat as it  impacts the die itself and discusses much of it here . The extensive experiment was  mostly run with hot-striking for what it is worth, though he acknowledges cold was used too.

It's quite a fun article, taking you through the whole process, metal contents, exact heats used, even his efforts  to engrave a die with a Metapontine ear of corn only  for it to come out looking more like a scorpion.

The overall conclusion though seems to be it helps make a well-struck coin, akin to @JAZ Numismatics comment above.

 

 

 

 

[Theodosius]

A really informative post, thanks! 

I love coins from Syracuse and some really beautiful examples have been posted here. 

John