Discussion: How are Security edges done on circulation coins

[beekar]

Friends,
   In this article, I am going to discuss about the sequence of putting security marks on high value Indian coins. Some where I have read that security marks are applied on high value Indian coins before those are fed to minting press. But articles by some Indian friends tell, that security marks are applied on high value Indian coins after those are minted in the minting press.
   Now the question is— Which of these 2 statements is correct?
a)   Security marks put before minting.
b)   Security marks put after minting.

[dheer]

Are we discusing proof and UNC in mint sets with milled / reeded edge?

[Figleaf]

Don't know what you mean by "security marks". Can you post a picture, please?

If a coin is punched after minting, the mark will be sharp and the area around it will be dull or even flat. A proof coin will look disfigured. Unless the coin is thick or very hard, the punch will create a slightly raised, flat area on the other side. If the flan is punched before minting, the mark will at best lose sharpness, at worst be partially or wholly obliterated by the strike. The area around it will be sharp.

In the paragraph above, I am assuming that the mark is applied to the obverse or reverse, not the edge.

Peter

[beekar]

Are we discusing proof and UNC in mint sets with milled / reeded edge?

I am not discussing about proof and UNC in mint sets. I am discussing about the security marks seen on the edge of 1 re regular coins issues during 1950 to 1988, on 5 rupees CN regular coins issued during 1992 to 2004 and 5 rupees FSS regular coins issued during 2007 to 2008.

[Rabi_R]

You may see Reply #4 by Figleaf in this discussion -

http://www.worldofcoins.eu/forum/index.php/topic,43764.0.html

[dheer]

I think we all agree it's a 2 step process.
In the first step there is milled or reeded edge.

So we first need to determine if the edges are milled; indicating a separate process or reeded, in which case it is achieved by collar die.

Generally in circulation strikes reeded edge is more common than milled. From Indian coinage point of view, I have observed more evidently reeded edge by collar die. One can see thin wire like structure coming up from edge above the surface of coins, consistent with collar die strike where the metal does not have more space to expand side ways, some expands upwards or downwards.

This also explains why some coins have plain edge, because the collar die used was plain; or certain type of errors where collar die is broken and results in incorrect reeded edge.

Now the security dot and slash, the depth is to much to have this as part of collar die strike. Hence it has to be a separate process.

Can this be before reeded edge by collar die; unlikely because the collar die would impart some of the reeding to security dots and dashes. Hence this has to be after the coin has been struck.

This is also consistent with getting a blank with plain edge as well as security edge dot and dashes but missing reeded edge.

If we go with the assumption that there is milled edge first, then security edge and then the coin enters into chamber for strike, to me this looks unlikely as plain edge would distort the milled edge due to the strike pressure; more so in cupro nickel. Steel may still withstand the pressure.

PS There are recent errors on Facebook that do not follow the above. Some may need a very long round about theory; some in my view are fakes. There are tons of fakes in error coins I have seen only in 2018.

[beekar]

You may see Reply #4 by Figleaf in this discussion

I fully disagree with Figleaf's reply given in #4.

I strongly believe that on high value Indian coins, security marks are applied on blanks before those are sent to minting press.

Please see the photo of an error coin posted below. It is a 1 re Mudra coin with Security mark on its edge. The weight of this coin is approximately 6 gms, which indicates that this coin was minted on a 6 gm planchet intended to mint 5 rs FSS coin. The security mark on its edge shows that it was minted on a 6 gm planchet on which security marks applied before it was fed to the minting press. Shall we tell that security marks were applied on this coin after it was minted?

[Rabi_R]

I fully disagree with Figleaf's reply given in #4.

I am not at all bothered whether you agree or disagree with him. Having said that, i have an observation on this statement -

The security mark on its edge shows that it was minted on a 6 gm planchet on which security marks applied before it was fed to the minting press.

How do you know that?

[beekar]

How do you know that?

It indicates a simple logic and thinking about the occurrence of this incident. Do u think that this 1 re mudra coin, after being minted on a 6gms fss planchet, was selected by mint operators and sent to the machine putting security marks on its edge and other minted coins were not sent to that press to get security marks?

Now I am going to to show u the photo of one 2 rs National Integration coin with Security marks on its edge. We all know that security marks are never applied on the edge of 6 gms Hendecagonal 2 rs National Integration coins. The weight of this cupro-nickel coin is approximately 6 gms, which indicates that this coin was minted on a 6 gm planchet prepared to mint 1 re  cupro-nickel coin. The security mark on its edge shows that it was minted on a 6 gm planchet on which security marks applied before it was fed to the minting press. Shall we think and argue that security marks were applied on this coin after it was minted?

[Rabi_R]

It indicates a simple logic and thinking about the occurrence of this incident. Do u think that this 1 re mudra coin, after being minted on a 6gms fss planchet, was selected by mint operators and sent to the machine putting security marks on its edge and other minted coins were not sent to that press to get security marks?

This one rupee coin, after being minted in a wrong planchet, escaped surveillance of quality control, was routed through RBI and through commercial banks and finally changed hands to reach you. How logical is that?

[dheer]

Errors do happen in mints. Error coins do come in to circulation. Some types of errors are more common than others.

[dheer]

I fully disagree with Figleaf's reply given in #4.

I strongly believe that on high value Indian coins, security marks are applied on blanks before those are sent to minting press.

Please see the photo of an error coin posted below. It is a 1 re Mudra coin with Security mark on its edge. The weight of this coin is approximately 6 gms, which indicates that this coin was minted on a 6 gm planchet intended to mint 5 rs FSS coin. The security mark on its edge shows that it was minted on a 6 gm planchet on which security marks applied before it was fed to the minting press. Shall we tell that security marks were applied on this coin after it was minted?

In your view when is the reeding done, separate process before security edge, or as part of collar die or after the coin is struck

[Rabi_R]

Errors do happen in mints. Error coins do come in to circulation. Some types of errors are more common than others.

I don't disagree at all, but those errors have to be minor errors only to be found after examination ( or after being told by some one). When the error is of the type being claimed above or errors that are no better than mutilations, questions do arise. A one rupee planchet and a five rupee planchet will be differentiated even by a five year old, even by a blind.

Before being minted, planchets are passed through two sieves. First sieve has larger holes than the size required to remove the larger sized planchets and second seive has smaller holes remove the smaller planchets. Quality check is applied at several stages throughout the minting process.

Just my opinion, what is being claimed above as error may not be error at all. That coin might have been minted for some purpose, not as part of regular production.

[repindia]

It indicates a simple logic and thinking about the occurrence of this incident. Do u think that this 1 re mudra coin, after being minted on a 6gms fss planchet, was selected by mint operators and sent to the machine putting security marks on its edge and other minted coins were not sent to that press to get security marks?

Now I am going to to show u the photo of one 2 rs National Integration coin with Security marks on its edge. We all know that security marks are never applied on the edge of 6 gms Hendecagonal 2 rs National Integration coins. The weight of this cupro-nickel coin is approximately 6 gms, which indicates that this coin was minted on a 6 gm planchet prepared to mint 1 re  cupro-nickel coin. The security mark on its edge shows that it was minted on a 6 gm planchet on which security marks applied before it was fed to the minting press. Shall we think and argue that security marks were applied on this coin after it was minted?

Your logic in stating this is faulty and is contradictory if you look at it a different way. If all blanks were to get the security edge done before being struck then those planchets will go to the respective dies-- in this case Rs 5 ones and in normal production process not routed to Re 1 or Rs 2 at all! If you were a production manager and have a protocol of only getting the Rs 5 coins from the security edge machine to the Rs 5 dies location then you will never route them to Re 1 and Rs 2!

On the other hand we have seen enough Rs 5 coins having reeded edges. Ask yourself why if that. @Figleaf's reply provides the answer. The edge reeding was applied through the collar when striking with the dies and then the coins are run through the security edge machine. There are many instances where there is a very faint center mark on the reeded edge and in most cases this process is skipped altogether creating these Rs 5 error coins. They are considered a variety but are in fact errors.

Please note that in all these cases we see security edge on reeded edge one and never ever reeded edge over security edge. There are some blanks where I have seen security edge and they have the reeded edge missing. These might have missed getting struck and went to the security edge application.

Many mints the world over operate this way and unless we go to the Indian mints and check I suppose they would be doing it the same way.

This is why study of errors is so interesting that it gives us clues about the minting process.

Regarding the Re 1 and Rs 2 coins having edge lettering, they could also be taken to the edge lettering after they were struck. This could be due to an error in process but more likely done on purpose for the benefit of dealers, though some might have escaped to circulation.

[@josephjk]

This is a planchet for a 1 rupee coin. The security edge is applied before the minting and the reeding is likely imprinted from the collar during minting