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Pillar of the Community
Australia
1150 Posts |
Please let me know about this coin it seems that the copper is showing on this coin or ram has used a old copper die.  Obverse also on neck and face of Queen. 
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Moderator
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32709 Posts |
@all, can you please post the weight too? That can help with figuring out if something is an off-metal strike. Thx.
"If you climb a good tree, you get a push." -----Ghanaian proverb
"The danger we all now face is distinguishing between what is authentic and what is performed." -----King Adz
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Pillar of the Community
 Australia
1150 Posts |
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Pillar of the Community
 Australia
1150 Posts |
 I weighed the capsule first. 
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Pillar of the Community
 Australia
1150 Posts |
0.21g - 0.23g under normal weight.i think
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Bedrock of the Community
Australia
21593 Posts |
Typical result as pictured, for any copper nickel coin, upon recovery from in-ground soil burial, after a year or more, depending on soil conditions.
Weigh another 20 Cent coin - the results should be the same. - I suspect that the scales may be a tad out of adjustment.
Edited by sel_69l 01/01/2023 11:17 pm
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Pillar of the Community
 Australia
1150 Posts |
Lol most coins differ in weight, but not by this much anyway I will check the scales as well.
Edited by Allcoinage 01/01/2023 11:37 pm
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Pillar of the Community
 Australia
1150 Posts |
This coin is normal in weight so definitely not copper just probably toning and my scales are fine. thanks
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Pillar of the Community
 Australia
1150 Posts |
Just to let yous know I weighed a 2022 Australian 20 cent and it was 14.42g on scale minus capsule 11.12g
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Bedrock of the Community
Australia
21593 Posts |
From OP's scales, weight difference between coppery looking coin and the 2022 coin is 0.03 grams.
It would be a fair to conclude that both coins are standard.
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Moderator
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16181 Posts |
Quote: ...or ram has used a old copper die. Um, no. 1. Dies cannot impart colour to a coin. Dies can impart "polish", but not colour. Colour is a property of the metal the coin is actually made from. 2. Coin dies are never, ever made of copper, or bronze. It's just too soft, it would deform out of shape after just a few presses. Even in ancient times, coin dies were made of the toughest steel they could manufacture. And there are no lumps of copper just sitting about the place they might "accidentally" make a die out of. And I would agree with the above posters as to the cause: post-mint environmental damage, not a mint error. Finally, you don't need to do that with the balance - it's just adding imprecision, and forcing us to do unnecessary maths. Just place the coin directly on the balance, or, if you're reluctant to do that, zero the balance while just the coin holder is sitting on it.
Don't say "infinitely" when you mean "very"; otherwise, you'll have no word left when you want to talk about something really infinite. - C. S. Lewis
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Pillar of the Community
Australia
998 Posts |
Yes,as I've posted before one of the multitude of causes of discoloring on Coins is moisture and carpet such as Coins left under floormats in cars.
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Pillar of the Community
Australia
1575 Posts |
Since the coin is a Copper-Nickel alloy and copper is less reactive than nickel it's possible the nickel reacted with an outside reagent leaving behind the copper. This certainly happened in some ancient coins where the copper reacted leaving a higher amount of silver near the surface.
Edited by David Graham 01/25/2023 2:38 pm
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Pillar of the Community
 Australia
1150 Posts |
Maybe the layer of nickel was not the standard amount because if it was buried the coppery look would be dull.
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Pillar of the Community
Australia
1575 Posts |
Quote:
Maybe the layer of nickel was not the standard amount because if it was buried the coppery look would be dull.
There is no layer of nickel in the minted coins. The alloy is a homogeneous mixture of copper and nickel as created when the two metals were melted together during the production process. As I said, it may be possible to create a copper 'layer' post mint via a chemical reaction that selectively removes the nickel from the alloy near the surface.
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