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 Replies: 27 / Views: 4,501 |
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Pillar of the Community
 United States
2745 Posts |
Here's another rim photo  Here's an example of a PCGS graded coin. Does no one see similarities here?   |
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Pillar of the Community
United States
3237 Posts |
It's definitely possible, CoinHI. Sadly, it's far above my pay grade to say with certainty. These annealing errors really separate the true experts like Mike Diamond from the serious enthusiasts like ourselves. Perhaps you can message him and ask him to weigh in?
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Bedrock of the Community
Australia
21788 Posts |
I have my doubts about off color copper nickel coins.
Too easily produced by a range of artificial or accidental means.
It is possible to produce a nice even brown or even a nice golden tone on a copper nickel coin, by direct contact soil burial. There have been quite a few pictures of metal detector finds posted here with the CCF, that show quite a range of colors found on coins recovered from burial.
I imagine that such toning could be produced far more evenly by dipping in the right sort of chemical solution.
I won't indicate the chemistry of the types of solutions, because too many may get some wrong ideas on how to do this.
Can be done with mint fresh uncirculated coins or with circulated coins.
Heating copper nickel coins to red heat turns them black. Copper nickel coins recovered from the ashes of fires also exhibit dark colors.
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Pillar of the Community
United States
2739 Posts |
I was asked to pipe in. I lean toward an improper annealing error due to the presence of sharply demarcated islands of exposed cladding amidst a sea of copper-colored metal. It's difficult to get this effect with environmental exposure. However, since the coin doesn't retain much mint luster, I cannot be certain of my diagnosis.
Error coin writer and researcher.
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Pillar of the Community
United States
3237 Posts |
@mikediamond thanks for chiming in! This is great info to have about the islands of exposed cladding.
Edited by SamCoin
06/02/2021 7:17 pm
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Pillar of the Community
United States
2745 Posts |
Thanks for taking a look Mike. Thanks also for the eloquent expansion on the clad island analogy.
Would be interesting to see a time lapse video of this (possible) error happening.
"Pride is yoked with callous behavior, as humility is with compassion." St. Gregory Palamas Top Finds - 1969-S 1c FS-101 http://goccf.com/t/477681 1976 D WQ FS-101 http://goccf.com/t/382777 - 1968 D 1c FS-801 http://goccf.com/t/422254Cool clashed dies - 1972 D 1c http://goccf.com/t/429855&SearchTerms=CCLStruck-In Rim Burr - 1969 S 1c http://goccf.com/t/425587&SearchTerms=burrFloating (Type II) Counterclash - 1978 D 1c http://goccf.com/t/434991&SearchTerms=1978 |
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Pillar of the Community
Canada
6244 Posts |
For the Nickel it is this: Quote:
Stress relieving is used to remove or reduce stresses in work hardened alloys. The stresses are relieved without causing recrystallization in the grains by heating to 800-1600°F.
Annealing is when an alloy is heated (usually to 1300-2200°F), the temperature is maintained for a while, then cooled. This treatment recrystallizes the grain structure. Annealing totally eliminates any stresses in the material, causes reduced tensile strength and improves ductility.
Solution annealing is a high temperature anneal (2100-2400°F based on composition) specific to certain alloys. It puts any carbides that have formed completely back into the solution and creates coarse grain size to enhance stress rupture properties.
Age hardening uses heat (800-1600°F) to change the solubility of an alloy that contains elements that promote this. Aging causes certain phases to precipitate at certain temperatures to increase strength. For this precipitation to happen, alloys must be kept at these high temperatures for extended amounts of time. This extended time is what is referred to as "age". The collors for different temperatures for Nickel it is this: (A) Without heat treatment; (B) 450°C; (C) 500°C; (D) 550°C; (E) 650°C; (F) 750°C.  So an annealing start with 800 degrees. Can some one say PCGS is wright? Edited by silviosi
06/03/2021 10:31 pm
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Pillar of the Community
United States
2745 Posts |
I'm not sure I understand the question Silviosi but the 5c color looks like choice "F"?
"Pride is yoked with callous behavior, as humility is with compassion." St. Gregory Palamas Top Finds - 1969-S 1c FS-101 http://goccf.com/t/477681 1976 D WQ FS-101 http://goccf.com/t/382777 - 1968 D 1c FS-801 http://goccf.com/t/422254Cool clashed dies - 1972 D 1c http://goccf.com/t/429855&SearchTerms=CCLStruck-In Rim Burr - 1969 S 1c http://goccf.com/t/425587&SearchTerms=burrFloating (Type II) Counterclash - 1978 D 1c http://goccf.com/t/434991&SearchTerms=1978 |
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Pillar of the Community
Canada
6244 Posts |
F is very black. Was not a question, just show the color change of the Nickel at different temperatures. then other thing, after plating or cladding no coin will be anneal, conclusion: I see it is impossible to have this color if no exterior agent will contact with.
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Pillar of the Community
United States
1667 Posts |
Environmental damage in my opinion and not a well cared for coin to begin with. The edge is the same color as the rest of the coin. So either we have a well circulated annealing error with no luster and environmental toning to boot, or we have a well circulated environmentally damaged coin.
In the end only the determination on the slab if it was sent for grading would clarify this. But what I know is real annealing errors have clean edges, and they still have mint luster although it's cloudy, it's still there.
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Bedrock of the Community
United States
62064 Posts |
I finally found this thread. I save the information and wanted to put it all on one image to include in my files and time got a away from me.  |
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Pillar of the Community
United States
549 Posts |
You are going to have to send it in. After all this, I say ED.
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Replies: 27 / Views: 4,501 |
First Page
Posted 06/02/2021 11:53 am
