Coin Minting Process [solved]

Hello,

I think it would be interesting to have a field for the minting process of a coin with some basic options:

- Cast
- Hammered
- Milled

Maybe even some extra details:

- Cast
- Hammered
- Milled (screw press)
- Milled (roller press)
- Milled (industrial)

Best,
strato

Hello,

There is now a field for the manufacturing technique (minting or printing process).
See this hammered coin for example: https://en.numista.com/catalogue/pieces171184.html

The possible values for coins, tokens and medals are the following:

• cast
  
• hammered
  
• milled
  
• engraved
  
• countermarked
  
• counterstamped
  
• cut
  
• roller milled
  
• incuse
  
• klippe
  
• bracteate
  
• scyphate
  
• wire
  
• cob
  
• bean
  
• bullet
  

The possible values for banknotes and paper exonumia are the following:

• intaglio
  
• letterpress
  
• screen printing
  
• lithography
  

Multiple values may apply for a single coin, banknote or piece of exonumia.
It's possible to add free-text details for specific processes.

Many of them are not techniques but forms (or are they called differently on the coin pages).
Bracteates and scyphate where hammered, klippe milled etc., also what's the difference between countermarked and counterstamped?

Quote: "Idolenz"​Many of them are not techniques but forms (or are they called differently on the coin pages).
​Bracteates and scyphate where hammered, klippe milled etc., also what's the difference between countermarked and counterstamped?

​Totally agree. Most of them are just non-sense.

Thank you, Xavier! Great to see this implemented

Quote: "Idolenz"​Many of them are not techniques but forms (or are they called differently on the coin pages).
​Bracteates and scyphate where hammered, klippe milled etc., also what's the difference between countermarked and counterstamped?

​Yes, some are forms, but they result from a particular step in the manufacturing process. Here are the working definitions, we should probably have a numisdoc for these:

Cast. Coins made by pouring melted metal into a mold. Casting is also used for manufacturing blanks for stamped coins. E.g. Celtic potin.

Incuse. Hot blanks are stamped on an anvil die using a sharp hammer die with no design, resulting in an incuse obverse. Blanks are usually cast and crude. E.g. early coins from Mysia, Lydia and other Greek city states.

Hammered. Blanks are placed between two dies, and stamped by hitting the upper die with a hammer by hand to impress a design on both sides. Most coins up to the 17th century.

Bracteate. Thin silver sheet is placed on an engraved anvil die and struck with a blank hammer die lined with a soft material, such as leather or lead. As a result, the reverse of a bracteate is an incuse mirrored image of its obverse. Usually, coins were cut to shape after minting, but occasionally blanks were also pre-cut.
Mostly, mediaeval coins from Germany, Bohemia, Switzerland, and Austria.

Scyphate. Hand-hammered coins with a pronounced curved (“bowl”) shape. The curvature was produced either with curved dies or during a separate process, after stamping flat planchets. The curvature may have been a security measure, or may have been used to increase the stiffness of the thin planchets being used. Mostly produced by mints in the Byzantine empire and successor states.

Klippe. Milled or hammered coins with polygonal shapes, usually square or octagonal, stamped either using round or polygonal dies. The blanks are cut from sheets and the polygonal shapes have the advantage of producing less residue needing to be remelted. Originally issued under unfavourable conditions, such as sieges, but later as regular or presentation coinage as well. Klippe have been minted from the Antiquity, but the golden age was in 16-17th centuries in Austria, Germany, and Switzerland.

Wire coins. Hammered coins with blanks prepared by flattening small metal wire cuts, which are then stamped with two dies. This results in slightly elongated coins, often showing traces of the original wire. Mostly Golden Horde, Russia, and Northern Europe coinage.

Cobs. Hand hammered coins with crude dies and irregular blanks cut from a lump of metal to an appropriate weight. Mostly used in the Spanish colonial empire.

Milled (also known as machine-struck). Hot blanks are pressed between two dies with a mechanism. Different types of mechanisms have been used: screw, balancer, lever, impact, or toggle presses among others, either human-, animal-, steam-, or electricity-powered. Introduced circa 1550. Most coins since the industrial revolution.

Roller milled. A thin strip of metal is passed between two rotating cylindrical dies that impress the design. Individual coins are then cut to shape from the strip. Coins can be easily identified by the slight bent shape resulting from the rolling process.
Originated in Hall in 1567, and was used in Cologne from 1568, Dresden from 1574, Kremnica from 1577, Danzig from 1577, Segovia, and other mints.

Counterstamped. An existing coin is machine-stamped with an additional design. Usually two dies are used to impress the design on both sides. For example, early Jamaican coins.

Countermarked. An existing coin is hammered with a punch that impresses a simple design. The mark is usually applied randomly on one side of the coin only. Also referred to as punchmarked coins, when stamped with several individual punches smaller than the blank, placed randomly, frequently overlapping and falling off the edge. The blanks are usually cut from sheets.
Mauryan coinage from 500-100 BC; Swedish plate coins.
Countermarks have be used since the Antiquity, mostly for provisional coinage.

Engraved. Blanks are incised by cutting grooves with a sharp tool called a burin or with a spindle. The process can be manual or numerically-controlled. Mostly used for personalising medals. It may be only used partially on one side, or for the entire piece.

Quote: "Idolenz"​Many of them are not techniques but forms (or are they called differently on the coin pages).
​Bracteates and scyphate where hammered, klippe milled etc., also what's the difference between countermarked and counterstamped?

The manufacturing technique intends to describe not only the way coins were minted (hammered, milled or cast), but also how the flan was prepared and which post-process was executed (cut, countermarked, etc.).​

Bracteates, scyphates, klippes, etc. are coins with a specific shape due to the way their flan was produced, before being hammered or milled. These techniques can be considered as subtypes of hammered coins or milled coins.

Of course the technique is closely related to the shape. For a bracteate for example, I would expect the shape to be "round (irregular)" in most cases, with a manufacturing technique "bracteate". Then, bracteates can reliably be searched by "shape: any round" or "technique: any hammered" or "technique: bracteate" (search by manufacturing technique will be added soon).

Scyphate, cob and klippe are the 3 values that are currently both listed as shapes and manufacturing techniques. Their specific shape is the result of the specific way their flan is prepared, which is part of the manufacturing process. Probably we could now remove cob and klippe from the list of shapes and use "square", "octogonal" or "irregular" instead.

While I like this implementation, I share the others' concerns on how not everything is actually a technique.

Take "Bracteate", for example. While the process to make Bracteates is distinct, a Bracteate is not a process--it is a result of that process. And I think that is where the problem is coming from: we are using the result to describe the process, which doesn't seem right.

Because all Bracteates are hammered (as this is the result of a specific type of hammering), I think putting that term in parenthesis would work better. I am thinking something like this:

Cast
Counterstamped (*)
Countermarked (*)
Engraved
Hammered
Hammered (bracteate)
Hammered (cob)
Hammered (incuse)
Hammered (klippe)
Hammered (scyphate)
Milled
Milled (cut)
Milled (klippe)
Rolled milled

Another possible solution would be to give two separate fields: one for Techniques and the other for Results. That way, someone could select "Hammered" and "Cob", and "Hammered (cob)" would automatically be generated (although I do not think that would necessarily help more than just listing everything in parenthesis).

(*) While I understand the difference, I anticipate a lot of confusion over these two being listed separately, and I cannot think of a way to minimize that confusion.

-----

That aside, there are three I am doubting:

The first is Bean... I just have no idea what that is.

The next two are "Wire" and "Bullet"--these are neither techniques nor results, but are rather things which the coins were created by (and so, if we were to include those two, I imagine "Sheet" and "Ingot" would be just as valid). These seem like something that, if we really needed it, could use an independant field, although I think this kind of information would be better kept to the Comments section.

And with that being said, I would worry about getting too detailed with this field (like including what things were made with) because this field could get very crowded. If we really wanted to get detailed, we could include, Baked or Glazed but those tend to depend on composition; we could also add Enamled, Inset, Incased, and Coloured, but I think those would work better as sections under Composition, even though there are specific processes for each of them.

-----

I agree with removing Cob and Klippe from the Shape section (I suggested removing Klippe a while ago).

And I will end this by suggesting the addition of one more under coins.

• Printed (https://en.numista.com/catalogue/pieces86312.html; https://en.numista.com/catalogue/exonumia296696.html)
  

I like the idea of adding bracteate, cob, etc. into brackets, as indeed these terms refer to the resulting coin, not the technique itself.
I just have a doubt about klippe, as I understand that it's often hard to tell whether the coin was hammered or milled, but still interesting to note that the coin is a klippe.
I also have a concern about "Milled (cut)": I would rather list "cut" separately, like "countermarked", since it can apply to any coin, independently of the technique used to produce the original coin (example: a cut cast coin or a cut stamped coins).

Here is the definition I have for bean coins (credit: Stratocaster):
"Hammered coins with blanks made by pouring molten metal on a piece of cloth immersed in hot water.
Mostly Japanese coins between 17th-18th centuries: mameitagin and chogin."

We should try to find a balance between listing all possible methods techniques and variants to prepare the flan, mint the coin, mint the edge, finish the coin, etc. and listing only relevant categories. I'm not sure where we should set the threshold: list ingots, enameled coins, coloured coins, printed, etc. or rather keep a shorter list without wire, bullet and bean?

Search by manufacturing technique is now implemented

Regarding Klippe: that is a good point--the difference would be difficult to tell. However, I imagine the difference would be just as difficult to differenciate as Counterstamped and Countermarked (you need to understand the history to tell which is which). With that being said, another issue I see is that we would not necessarily be able to view all Klippe coins together, if they are split under two different sections (and the same goes with Counterstamped versus Countermarked).

Regarding Cut: I was thinking of coins cut in half--those Chinese ones never crossed my mind, but I guess those definitely count as being cut. You also make a good comparision with it against Countermarked... perhaps we could make another catagory to group them together under, like "Modified"?

If we just have one list to select things from, that would mean the original process for making the coin does not matter as much as the modification, and if someone were interested in the original process, they could find the original coin to see what that one's process was. But if we had different lists for Process/Result/Modification, where you could pick things from each section, it would be possible to include the way the original coin was made in addition to the modification.

-----

Regarding Bean: that is very interesting--I never knew about that. But with this being a process for preparing the planchet, I would think to not include that within our current list as these work as Hammered coins, with the specific details working in the Comments section (for now, at least).

Regarding Printed: I honestly think this is just as valid as Milled or Hammered--it is rare, but it is definitely a process, hence why I think that one should be included.

With that being said, Punchmarked might also be valid (while Counterstamped / Countermarked are modifications on existing coins, Punchmarks are applied to blank planchets, and there are often many applied without a set pattern, specifically with Indian coins).

And I added Modified (holed) for coins like this: http://en.numista.com/catalogue/exonumia299653.html

-----

What follows will be different modifications on the above list I made. The first two would be if we had a singular list to select things from:

Cast
Engraved
Hammered
Hammered (bracteate)
Hammered (cob)
Hammered (incuse)
Hammered (klippe)
Hammered (scyphate)
Milled
Milled (klippe)
Modified (counterstamped)
Modified (countermaked)
Modified (cut)
Modified (holed)
Printed
Punchmarked
Roller milled

Cast
Engraved
Hammered
Hammered (bracteate)
Hammered (cob)
Hammered (incuse)
Hammered (scyphate)
Milled
Modified (counterstamped / countermarked)
----- (Maybe?)
Modified (cut)
Modified (holed)
Printed
Punchmarked
Roller milled
Variable (klippe)

And this one would be if we had multiple lists to select from:

Process
Cast
Engraved
Hammered
Milled
Printed
Punchmarked
Roller milled
Variable
Result
Bracteate
Cob
Incuse
Klippe
Scyphate
Modification
Counterstamped
Countermarked
----- (or Counterstamped / Countermarked)
Cut
Holed

With this last one, I think a list like that would definitely help in the Advanced Search (similar to how, in Composition, you can search for only Precious metals, but that is not an option when modifying a page). That way, you could search for Klippe coins regardless of the Process; or you could search for Hammered coins regardless of the Result (so you would see Bracteate and Cobs within the same list).

With that being said, that same list could be applied to the Creation/Modification page. I am thinking something like this:


While the first two options would work as a single list under the Technical data section, if we went with the third option, I think it would look nicer under its own section. With that option, we could get something like "Hammered (scyphate; countermarked)", but that means we would need three different sections to do it, which means the Techniques would overcrowd the Technical data section. Giving it its own section, it is out of the way, and there is room to expand upon the techniques (like if we were to include how the planchet itself was made).

(Although "Modification" would probably work better as the tag system because you could mix-and-match different types of modifications; you cannot necessarily mix-and-match "cob" and "bracteate", hence why that list would be a drop-down.)

Quote: "Xavier"​I like the idea of adding bracteate, cob, etc. into brackets, as indeed these terms refer to the resulting coin, not the technique itself.

I very much prefer the simplicity of the current list. While I understand that "bracteate" is not a technique, I think it keeps things clean and "at a glance" in the Features panel. If we add multiple tags everything looks fine and has all the functionality needed:
Technique Hammered, bracteate
Technique Milled, counterstamped
Technique Hammered, klippe

Quote: "Xavier"​​We should try to find a balance between listing all possible methods techniques and variants to prepare the flan, mint the coin, mint the edge, finish the coin, etc. and listing only relevant categories. I'm not sure where we should set the threshold: list ingots, enameled coins, coloured coins, printed, etc. or rather keep a shorter list without wire, bullet and bean?

​Should we have a guideline for new techniques? e.g. minimum 100 coins (or exonumia ?) from at least two different countries? Then some more processes will likely qualify (firing, injection moulding, milling, routing, 3D printing).

Quote: "Xavier"​I also have a concern about "Milled (cut)": I would rather list "cut" separately, like "countermarked", since it can apply to any coin, independently of the technique used to produce the original coin (example: a cut cast coin or a cut stamped coins).

​Oh, and speaking of modifications, there are a few we will need for banknotes as well.

• Cut
  
• Overprinted
  
• Perforated
  

Quote: "Sulfur"​Oh, and speaking of modifications, there are a few we will need for banknotes as well.
​

• Cut
  ​
  
• Overprinted
  ​
  
• Perforated
  ​
  

​

​Thank you
I added those.

Quote: "stratocaster"​​Yes, some are forms, but they result from a particular step in the manufacturing process. Here are the working definitions, we should probably have a numisdoc for these:
​
​Cast. Coins made by pouring melted metal into a mold. Casting is also used for manufacturing blanks for stamped coins. E.g. Celtic potin.
​
​Incuse. Hot blanks are stamped on an anvil die using a sharp hammer die with no design, resulting in an incuse obverse. Blanks are usually cast and crude. E.g. early coins from Mysia, Lydia and other Greek city states.
​
​Hammered. Blanks are placed between two dies, and stamped by hitting the upper die with a hammer by hand to impress a design on both sides. Most coins up to the 17th century.
​
​Bracteate. Thin silver sheet is placed on an engraved anvil die and struck with a blank hammer die lined with a soft material, such as leather or lead. As a result, the reverse of a bracteate is an incuse mirrored image of its obverse. Usually, coins were cut to shape after minting, but occasionally blanks were also pre-cut.
​Mostly, mediaeval coins from Germany, Bohemia, Switzerland, and Austria.
​
​Scyphate. Hand-hammered coins with a pronounced curved (“bowl”) shape. The curvature was produced either with curved dies or during a separate process, after stamping flat planchets. The curvature may have been a security measure, or may have been used to increase the stiffness of the thin planchets being used. Mostly produced by mints in the Byzantine empire and successor states.
​
​Klippe. Milled or hammered coins with polygonal shapes, usually square or octagonal, stamped either using round or polygonal dies. The blanks are cut from sheets and the polygonal shapes have the advantage of producing less residue needing to be remelted. Originally issued under unfavourable conditions, such as sieges, but later as regular or presentation coinage as well. Klippe have been minted from the Antiquity, but the golden age was in 16-17th centuries in Austria, Germany, and Switzerland.
​
​Wire coins. Hammered coins with blanks prepared by flattening small metal wire cuts, which are then stamped with two dies. This results in slightly elongated coins, often showing traces of the original wire. Mostly Golden Horde, Russia, and Northern Europe coinage.
​
​Cobs. Hand hammered coins with crude dies and irregular blanks cut from a lump of metal to an appropriate weight. Mostly used in the Spanish colonial empire.
​
​Milled (also known as machine-struck). Hot blanks are pressed between two dies with a mechanism. Different types of mechanisms have been used: screw, balancer, lever, impact, or toggle presses among others, either human-, animal-, steam-, or electricity-powered. Introduced circa 1550. Most coins since the industrial revolution.
​
​Roller milled. A thin strip of metal is passed between two rotating cylindrical dies that impress the design. Individual coins are then cut to shape from the strip. Coins can be easily identified by the slight bent shape resulting from the rolling process.
​Originated in Hall in 1567, and was used in Cologne from 1568, Dresden from 1574, Kremnica from 1577, Danzig from 1577, Segovia, and other mints.
​
​Counterstamped. An existing coin is machine-stamped with an additional design. Usually two dies are used to impress the design on both sides. For example, early Jamaican coins.
​
​Countermarked. An existing coin is hammered with a punch that impresses a simple design. The mark is usually applied randomly on one side of the coin only. Also referred to as punchmarked coins, when stamped with several individual punches smaller than the blank, placed randomly, frequently overlapping and falling off the edge. The blanks are usually cut from sheets.
​Mauryan coinage from 500-100 BC; Swedish plate coins.
​Countermarks have be used since the Antiquity, mostly for provisional coinage.
​
​Engraved. Blanks are incised by cutting grooves with a sharp tool called a burin or with a spindle. The process can be manual or numerically-controlled. Mostly used for personalising medals. It may be only used partially on one side, or for the entire piece.

​As Numisdoc no longer exists, is there a possibility to add the definitions somewhere? Maybe in the guidelines or elsewhere?

In addition, here are some definitions (in French) for banknote manufacturing techniques. For the PDF, I can provide the document via a google docs if you wish.





If there is a possibility to add definitions somewhere, I can take care of providing synthesised definitions by taking my sources from the two documents above.