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 Replies: 8 / Views: 1,298 |
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New Member
Canada
18 Posts |
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Moderator
 Australia
16808 Posts |
Quote:
Was it put in a fire, buried, exposed to grease, or did someone take a black marker to it? Any of those could cause a coin to turn black. A soak in acetone would remove the black if it were from marker ink, or soil, or grease that was causing the colour change. Coins can also turn dark if left in a chlorinated pool or fountain. Ultimately, it's always tricky to say with confidence exactly what caused post-mint damage on a specific coin. We weren't there to watch it happen. Being able to replicate the damage on another coin by some technique is not necessarily proof that that technique is what caused the damage, since (as in this case) similar damage can arise from multiple possible causes. 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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Bedrock of the Community
United States
94367 Posts |
That pretty much covers it!  to the CCF! |
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Pillar of the Community
 Canada
1761 Posts |
 @Coinh3ad |
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New Member
 Canada
18 Posts |
Thank you for the insight and the welcomes! That is the best way to think about the situation, we weren't there and there is no need to speculate when there are so many other cool coins to look at.
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Bedrock of the Community
United States
73747 Posts |
Environmental Damage of some sort. PMD. Not sure what caused it, but it's damage. Errers and Varietys.
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Moderator
Canada
10456 Posts |
It might be a legit planchet error. http://goccf.com/t/242098&whichpage...hTerms=blackThe planchet was heated - but before the strike. Some time ago I spoke to the manager of the plating plant at the Winnipeg mint, and these happen because planchets get struck in the large dryers after the plating baths. After several to many drying cycles, they turn darker, then they get unstuck and are struck like a normal coin. "Discovery follows discovery, each both raising and answering questions, each ending a long search, and each providing the new instruments for a new search." -- J. Robert OppenheimerContent of this post is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported License. See: http://creativecommons.org/licenses...0/deed.en_USMy eBay store
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Pillar of the Community
Canada
5585 Posts |
SPP, I'm glad that you got to the crux of the "blackening" problem and, from a mechanical engineering standpoint, really makes sense. Thanks
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Pillar of the Community
Canada
514 Posts |
I was going to say it's a plating error of sorts.
I have observed this before.
Thanks SPP-Ottawa for sharing your knowledge!
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Replies: 8 / Views: 1,298 |
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Posted 01/23/2024 7:42 pm
