I noodled a $200 bag of 50¢ today.Found a couple of nice 1988 "tall ships" and two decent CoF.
But this one has me puzzled. Looks like it it pressed in, not hammered -opposite edge doesn't show any undue damage. It is circular impression and rim is slightly raised on one edge. The spacing of the ridges is well more than a usual milled edge -about 1mm.
It is a 1981 but that is probably not relevant.
Any theories?
(https://www.australian-coins.net/gallery/albums/userpics/10055/160/DSCF6284.JPG)
(https://www.australian-coins.net/gallery/albums/userpics/10055/160/DSCF6285.JPG)
P.S. I also found a 2010 upset but worn.
The question has been asked many times re this sort of damage on the 50c pieces.
To date, I think people have used coin machine damge or some such thing.
I have found/seen many of the same when I have been noodl;ing but never saved any of them because I was finding to many with the same damge.
When someone can show how this damage was done, I would be very interested.
Over a few years and also a few instances of seeing coins like this, the consensus of opinion was that it's caused by a some sort of coin handling/vending machine.
A few instances have also appeared on CCF, several different years involved.
Hi Jeff, that is interesting.
The question is: whether the fault was part of the planchet stamping, occurred during pressing or in some process after minting?
Once stamped the coin is pretty tough so a fair bit of force would be required to press out the ribbed bit post mint.
There would have to be damage or bruising opposite on the supporting surface, you note there is not.
It does not look like the ribbing is cut away by a machining process.
That makes me think it is part of the pressing of the coin and some failure or obstruction in the collar die.
Now, I am assuming there that a collar die is used!
I do not have enough knowledge of stamping of 50c pieces to know the collar arrangement.
I would be think that someone working at the mint reads these posts and could comment on the pressing process.
Fred.
I don't remember what years the CCF examples were but it has appeared a few times and assuming different years, a damaged collar die seems pretty unlikely.
What does it weigh? If it's underweight it might be planchet damage.
Correct weight. Judging by metal displacement it looks like after stamping event.
I just had a closer look at the opposite edge and there is damage there, more than elsewhere. A chip, or two, and what looks like nail punch marks.
(https://www.australian-coins.net/gallery/albums/userpics/10055/160/DSCF6290.JPG)
Ah well intentional damage does seem the likely culprit then.