Discussion: How are Security edges done on circulation coins

[Rabi_R]

What is the source of your images? Mints in India don't share images of planchets.

[@josephjk]

What is the source of your images? Mints in India don't share images of planchets.

You are funny

[Rabi_R]

......... more likely done on purpose for the benefit of dealers, though some might have escaped to circulation.

Not exactly, done solely as part of State policy and was supposed to be red taped inside mint premises, some how escaped through a rat burrow, which in English may be called pil....ge.

[repindia]

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

Welcome back Joseph! Or at least I am seeing you after a long time here becoming active here only recently.

Does your third picture of security edge with reeded edge of a blank planchet? I doubt it.

The second picture of only security edge would have happened as I stated in my earlier post...coin did not get struck and with others went to the security edge application.

[repindia]

You are funny

You really were inactive here. Missing out on all the fun. 

[@josephjk]

I got distracted with FB and Travancore 
Glad to be back

[@josephjk]

Does your third picture of security edge with reeded edge of a blank planchet? I doubt it.

The second picture of only security edge would have happened as I stated in my earlier post...coin did not get struck and with others went to the security edge application.
[/quote]

The second picture (plain edge) is of the blank planchet
The bottom picture (with reeding) is a minted 1 rupee coin

I concluded from the two that the security edge is applied before minting and the collar then presses the reeding while the coin gets minted. This applies for that particular type of 1 rupee coin

The five rupee coins like you mentioned, seem to follow a different process of getting reeded from the collar during minting and then the security edge applied later. I've seen a lot of error coins where the security edge is either completely off centered or partly applied, some at very strange angles

[dheer]

Good to see you back...

I also have a planchet with security edge, unstruck. In my view this is also possible that coin didn't enter the striking chamber, but made it afterwards to security edge.

If you are agreeing that reeding is part of strike by collar die, then there are cases where the security edge is not deep enough. One should have seen the reeding on the high points of security. In fact in most rs 5, the reeding and security are at same depth. So if security was first and then reading, one should have at times seen light imprints of reeding on high points of security.

[repindia]

I was going some research on Google and one reference says security edge applied during the upsetting process. This might be true from a production standpoint to eliminate one extra process and as Joseph says the Re 1 coin might have had it this way. The evidence we see for the Rs 5 coins is contrary to the fact. If it was done during upsetting then when are there reeded edge coins? Granted during upsetting the security edge mechanism might have been absent so the reeded edge, but then there are a lot of coins as other posters say where there is partial or weak security edge. Editing my answer-- there is no way of the security edge mechanism to be absent at upsetting...it has to be in the process itself. One possibility that the coin went through the wrong upset mill...very low possibility of that.

This would have to be done differently for different coins. Does anyone here have any access to the mint production facility to find this out for us? Oh, I forgot most people here are not dealers. J/K 

[@josephjk]

It's always easier to discuss this with pictures.... these are 5 rupee coins and their edges.
From looking at them, it seems like the security edge was applied before the reeding was applied from the collar.
Seems like the reeding seems to have hit the high points in the security design.
I wonder if the foreign mints for this coin used the same process....

[dheer]

Thanks. This clears for me. I now agree that it is before.

First security marks and then reeded edge via collar die during strike.

It is surprising that I didn't get a coin that had such a clarity; or maybe I need to visit you to get a lesson in photography.

[Pabitra]

It is almost a standard practice ( there could be few exceptions) that the edge is made before the coin is minted or struck.
The security edge is not the most secure edge. The most secure edge is lettered edge and there is a great misconception that this is made by collar die.

Even 2 Euro coins, which use the lettered or engraved edge, make the edge first and the strike the coin.
Precisely due to this sequence of processes, they end up with wrong legend ( blank supplier sending the mixed up lot ) or upside down ( the blank ending with wrong side up) errors.

See

http://www.worldofcoins.eu/forum/index.php/topic,33947.msg225520.html#msg225520

http://www.worldofcoins.eu/forum/index.php/topic,1990

http://www.worldofcoins.eu/forum/index.php/topic,28801

As far as India is concerned, there is a mint who makes minor errors on demand, if you know the sources.
Trying to explain the minting process sequence, based on those errors, does not prove anything.

[repindia]

The pictures are very definitive and helps clear the matter. I have some error British India coinage in which the broadstruck struck out of collar coins do not have edge reeding but have the security edge is present. I was under the impression that this was a practice then and now changed. Now question is whether applying the security edge part of the upsetting mill or is it a two step process? We have enough Rs 5 examples to show that missed the security edge.

@Pabitra, the US dollar coins edge lettering is done after the coin is minted. This is widely documented and has resulted in some varieties-- no edge lettering or two types of edge lettering with different orientations (position A and B)

I don't know about the 2 Euro coins and perhaps @Figleaf might chime in.

[beekar]

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

In my view a coin gets its reeding from the collar die, when the coin is struck.

[beekar]

It's always easier to discuss this with pictures.... these are 5 rupee coins and their edges.
From looking at them, it seems like the security edge was applied before the reeding was applied from the collar.
Seems like the reeding seems to have hit the high points in the security design.
I wonder if the foreign mints for this coin used the same process....

Many thanks to @Josephjk for his explanation with nice photos. Now it is clear that security marks are applied before a coin is sent to the minting press and during the process of minting the coin edge gets reeded marks from the collar.