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 Replies: 38 / Views: 4,343 |
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New Member
 United States
40 Posts |
Correct, the recent edge pictures ARE NOT the coin in question... they are actual pictures of an acid damaged coin for reference - my coin edge is pictured in the first post along with a regular Kennedy half. As for the recent post by Tanman... So, you are saying that a coin dipped in acid will possibly react evenly through both copper and nickel alloy layers. This does not take into consideration 2 things... the first is that there would be some resistance to acid corrosion on the obverse or reverse from the coin sitting on that side while in acid or being in constant contact with a surface. Making one or the other side LESS affected by the acid, my coin is even on both sides. Not a strong argument, but something to consider. second and more importantly, IF the coin was in acid AND assuming the clad layer is of even thickness for the entire coin... wouldn't the clad nickel alloy layer STILL have edges like the example coin shown with the recessed copper? Think about it, the clad layer of a coin would have to be eaten away in such a manner that the edge would be deteriorated from left to right just as quickly as the coin is being eaten from top to bottom. All this before the copper was reached on either surface of the coin. Meaning the coin would have to be eaten away at the same width as diameter, all before exposing the copper on either surface. Since, FOR EXAMPLE; the half dollar is 30.6mm in diameter and 2.16mm in thickness. If the coin is then brought down to 29mm the thickness of the coin would ALSO need to be reduced by the SAME 1.5mm, making the half dollar 29mm in diameter and .6mm in thickness. IF that were the case the coin's copper core would clearly have been exposed. Now since I thought this out, I did measure the coin's diameter.. it is roughly 28.5mm. (there is about an eighth of an inch difference in the 2 coins diameter) This means by the acid approach the coin should only be .6mm in thickness or even non existent AND this would have clearly exposed the copper core. Please know that I am not trying to argue with anyone, I am very thankful that everyone is being generous and sharing their knowledge. I just want to make sure I understand what I do or don't have. AND as of now, I am 90% convinced that I DO NOT HAVE AN ACID DAMAGED COIN. Specifically because the copper edge is not sunken and my explanation of what would have had to happen to the thickness if the deterioration was constant for the entire coin. Just adding a reference to Tanman's weight numbers... if the weight of the clad layer is 37% of the coins weight, we can then say that the thickness of the clad layer is also 37% of the thickness. Since the coin would have had to have been eaten .75mm from any given side (1.5mm in all from the diameter); it would have also had to have been eaten .75mm from both the top and bottom. Given that the clad layer makes up only 37% of the coins thickness, it would have eaten through the entire clad layer ON BOTH sides if it was in acid or corrosive. (2.16mm x .37 = .799 round this to .8mm and divide by 2 for both top and bottom the clad layer can only be .4mm thick on either surface). Edited by Dennis omara
06/24/2020 6:51 pm
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Pillar of the Community
United States
1543 Posts |
Acid is not the only corrosive substance and I think assuming the deterioration would be consistent is incorrect.
If you look at the first picture, it seems the reeding sticks out past the rim of the coin. Imo that's a pretty good sign it is damaged.
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New Member
United States
40 Posts |
Well if you can describe a scenario where the clad layer and the copper core deteriorate equally to cause the edge to be uniform, and lack the recessed copper core like other acid coins; all while lacking the same "aggressive" behavior on clad surface layers... while still maintaining a consistently EVEN surface (no pitting or low spots)- I'm all for hearing it.
I do not think the edge sticks out anymore than a regular coin, all the pics in the first thread show this from several sides.
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Pillar of the Community
United States
1543 Posts |
Quote:
Well if you can describe a scenario where the clad layer and the copper core deteriorate equally to cause the edge to be uniform, and lack the recessed copper core like other acid coins; all while lacking the same "aggressive" behavior on clad surface layers... while still maintaining a consistently EVEN surface (no pitting or low spots)- I'm all for hearing it. To me, it appears you coin does not have an even surface and I supposed I described the edge poorly. On your first picture, on this thread, with the two edges side by side, the first 6 reeds are bordered on each side by the rim of the coin. It looks very similar to the second acid etched coin you posted. by the 7 or 8th reed the reeds have come back up to the rim on our right. Your coin is also noticeably thinner than the other half. |
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New Member
United States
40 Posts |
Fair enough, I have the benefit of having the coin in my hand to review.
The thinness of the coin is what drew me to a possible error. Having said that, the rim is clearly NOT perfect. I do agree that it has some questionable attributes. But with all that I have covered on the rate of deterioration, I am not sold this is an acid/corrosive coin.
Clearly it is not a normal coin but, keep in mind, this IS a circulated coin. I can pull 100 circulated half dollars that look worse than this coin, from grease strikes to dirt rot.
The stark reality of this coin is that for it to have been an acid dipped coin, it would have had to have been eaten away twice as fast from the sides as it was from the top or bottom. So, for this to be an acid dipped coin, it would either need to have a significantly recessed copper core OR the clad layer would no longer exist.
Now tell me why this can't be a foreign coin planchet (I have ruled out a blank planchet struck from quarter stock do to the 28.5 diameter - wrong stock right punch still would be correct diameter)? In 1975-76, the Philadelphia mint struck coins for Liberia... one such coin has a weight of 8.9 grams and a diameter of 28.5mm, it is also a nickel clad!
Edited by Dennis omara
06/24/2020 7:34 pm
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Bedrock of the Community
United States
62064 Posts |
Even silver can be reduced with acid:  |
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Pillar of the Community
United States
4406 Posts |
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there would be some resistance to acid corrosion on the obverse or reverse from the coin sitting on that side while in acid or being in constant contact with a surface. Making one or the other side LESS affected by the acid Is it possible for the coin to have been suspended in the acid instead of being placed face-down in it? Maybe held in the acid with tongs that only touched a small area on the face of the coin? Conducting experiments on coins in chemistry classes is very common as it is very easy to find exactly what metals some coins are made of, their weights, and their dimensions. Quote:
Since, FOR EXAMPLE; the half dollar is 30.6mm in diameter and 2.16mm in thickness. If the coin is then brought down to 29mm the thickness of the coin would ALSO need to be reduced by the SAME 1.5mm, making the half dollar 29mm in diameter and .6mm in thickness. Your math here is slightly wrong, but that doesn't matter. We're talking about a 3-dimensional object, you can't use 2-dimensional measurements like this. Putting a coin in acid wouldn't remove mm of metal, it removes mm^2 of metal. Removing 1mm of metal from the face of the coin is a lot more than removing 1mm from the edge. But none of that matters, as Conder pointed out before, the diameter has shrunk but the reeding is still present. A coin struck on an undersized blank WILL NOT have reeding as the blank cannot reach the collar (which adds reeding to the coin) unless it's properly sized. The only way that an undersized coin could still have the reeding, to my knowledge, is if the metal of the coin was evenly removed. Acid would do this. That previous post of mine was to show that a weight reduction of 23% would not completely remove the copper-nickel layer, which explains why no copper is visible through the faces despite a seemingly significant loss of metal, a point Pete brought up in a previous reply. Edited by Tanman2001
06/24/2020 9:35 pm
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New Member
United States
40 Posts |
"Is it possible for the coin to have been suspended in
the acid..."
So what should I look for on the coins surface that would indicate such a suspension, there would have to be some kind of residual mark.
"Your math here is slightly wrong, but that doesn't
matter..."
YES, it does matter, please show me YOUR formula and or logic for deriving the rate of deterioration from the coin. A blanket comment on my math with ABSOLUTELY nothing of substance to show that I'm wrong is... well, just blowing smoke. And a rather generic way to discredit someone.
I actually showed a .75mm deterioration for each side of the coin, hence 1.5mm for left to right and 1.5mm for top and bottom. I have the actual diameter of the coin, so I HAVE a known reference to start from. The size of the coin is so small that the surface contact area for the sides vs the top or bottom would be insignificant.
"Removing 1mm of metal from the face of the coin is a
lot more than removing 1mm from the edge..."
Yes I agree, but isn't the edge just a smaller version of the face, exposed to PROPORTIONATELY the SAME amount of acid per mm^2?
"But none of that matters, as Conder pointed out
before, the diameter has shrunk but the reeding is
still present. A coin struck on an undersized blank
WILL NOT have reeding as the blank cannot reach the
collar..."
Fair enough, but we are talking about a coin that is ONLY 1.5 to 2mm smaller than the collar for a half dollar. It is not grossly undersized like an actual quarter planchet would be at 6.4mm smaller. Doesn't the reeding get pressed into the sides, I guess we would have to know how deep the reeding on a half dollar actually goes to say that. Surely the pressure needed to imprint the reeding has to have an allowance for many things, and 1mm doesn't seam like that much.
"That previous post of mine was to show that a weight
reduction of 23% would not completely remove the
copper-nickel layer..."
Yes, I know why you used the weight example, but it actually is a good solid number to base things off. Knowing the weight of the clad portion of the coin allows us to determine the thickness of the clad layers. Which, as you have read, is a strong part of my argument on the rate of deterioration. The clad layers being no more than .4mm and the diameter being reduced by .75mm (1.5mm total) shows me that there is a strong reason to doubt the acid argument. Even if the rate of deterioration is different for the top and bottom vs the sides, there would be a tell tale lip of copper on the outside rim. As in the case of all solid metal coins, the rim is deteriorated by a greater amount, hence the lettering on the surface of these coins are worn near the edges.
Good points, but not sufficient in my mind. I do think it will take a lesson or twelve in chemistry for me to grasp something more than what I have described here - and that's not going to happen anytime soon. But the collar and the reeding is still insufficient for me, maybe not for everyone else, but for me.
Anyway I do not want to go back and forth, it looks like I will need to do some more research to quench my thirst here. I will try to find out what the actual depth of reeding is.
But thanks for your replies.
Edited by Dennis omara
06/24/2020 8:55 pm
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Pillar of the Community
Canada
3733 Posts |
50$ and a third party grader will solve this equation for you sorta, just a thought..
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New Member
United States
40 Posts |
Anacs is offering a special, 10 US coins for $109... free return shipping... ends in a few days! At least I will get 9 other coins graded that have hope! LOL |
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Pillar of the Community
United States
992 Posts |
Let us know how it turns out!
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Bedrock of the Community
United States
10635 Posts |
Quote:
50$ and a third party grader will solve this equation for you sorta, just a thought.. Could be an expensive lesson. Go for it! |
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Bedrock of the Community
United States
17884 Posts |
Quote:
Now tell me why this can't be a foreign coin planchet Well there is only one country that uses coppernickel clad planchets, and that's the US. There used to be two, the other one being Panama, but we were striking the Panama coins and using US coin planchets (Same sizes and specs for both countries.) |
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Pillar of the Community
United States
1566 Posts |
 Dennis To CCF. Dennis They say sometimes ya have to think out side the BOX. This is Not one of them times. Your coin is nothing but a Damaged coin save your time and money and stay in the BOX on this one. Happy Hunting  Edited by Daves Errors
06/25/2020 01:58 am
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Forum Dad
 United States
24175 Posts |
When you get the coin back contact me and I will unlock this topic so you can post pictures.  |
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Posted 06/24/2020 5:52 pm
