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 Replies: 10 / Views: 4,251 |
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Valued Member
Canada
448 Posts |
I recently purchased a lot of RCM coins and noticed 4 of them look a bit off.. the face of the coin appears off in color.. they look more of a bronze color that normal.  anyone ever seen this before or know what may have caused it |
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Pillar of the Community
Canada
798 Posts |
Yes, they tone that away if the clam has been left open in the sun for a long time.
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Pillar of the Community
 Canada
2360 Posts |
 I have seen the same at Canada Post with display coins in direct sunlight, nice copperish tone but it is a distraction and will affect resale value. You likely received a discount from issue price, but I see this Georgina Pope coin available on sale at CA for $29.95 now. I have a note in my coin book that says 2012 RCM annual report 3,154 of these sold. Seems like it should be worth more. If you intend to keep them, all is good, but they may be considered to be a details coin - toned with Post Mint Damage ( PMD). Edited by SilverDon
11/12/2017 06:52 am
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CCF Master Historian of USA Commemoratives
 United States
12264 Posts |
Coins that tone on their own (i.e., w/o someone using artificial means) are not generally considered to have post-mint damage. It is known that exposing the RCM's coins to prolonged sunlight (while they are in their capsule) can cause them to develop a golden tone - the toning might not be to the liking of all collectors, but I wouldn't consider the coins physically damaged. Collecting history one coin or medal at a time! (c) commems. All rights reserved.
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Pillar of the Community
Canada
2360 Posts |
Yes some toning is desirable but not usually on new
NCLT. In this case the toning is a discoloration
which is the damage, it is not as issued from the
mint and thus would require a seller to list the
coin as toned, which is an impairment. Toning
should occur over time. This coin is 5 years old.
I enjoy a nice natural toned silver coin.
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Pillar of the Community
United States
2408 Posts |
That is an interesting effect. Is the coin equally toned on both sides?
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Valued Member
 Canada
448 Posts |
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Pillar of the Community
Canada
2366 Posts |
Heard a dealer mention a couple of weeks back that he had some 2017 coins that had discoloured this way. In an enclosed mall so no direct sunlight on the display cases. Seems to have happened faster than usual. I've seen a number of 2012-2014 like this so previously figured it took a couple of years at least.
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Pillar of the Community
United States
2408 Posts |
Quote:
No. Just the one side. So yeah... this points to some kind of chemical interaction between the capsule/coin and prolonged exposure to light. It became more like a fantasy coin which may not appeal to most collectors. But I personally think it is very cool. The coin reminds me of the $3 Allegory 2013. |
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Pillar of the Community
Canada
2984 Posts |
Any prolonged exposure to light would likely discolour coins. Don't need to be direct sunlight. Similar to photos that fade from UV light.
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Pillar of the Community
Canada
665 Posts |
I have also seen this in dealer cabinets where coins are on display under artificial light.
Virtually all sources of light emit UV to some degree. The sun is the most obvious but Halogen, Fluorescent, Incandescent and LED all emit some UV. It is known that UV will cause silver to tarnish... This is not the same reaction as exposure to Oxygen which results in the familiar black Silver Oxide toning.
This is one of the reasons that Museums spend so much on lighting. Light sources that provide a correct color spectrum but also inhibit UV emissions are expensive.
Since this is only on one side of the coin, the exposure to light is the probable culprit as if it were a heat reaction with the capsule, the other side would carry some degree of the toning also.
There are a bunch of scholarly papers (well beyond my understanding) regarding the use of UV to ionize Silver for the anti-bacterial effects of Silver to preserve food etc. Since all Numismatic silver, contains copper in the alloy, even "pure" 9999 silver, it may be that the UV is causing the copper to shine through. Is there anyone who has a deep understanding of the chemistry of Silver and UV interaction?
That said... it is probably best to keep silver away from light sources and in the dark unless you have very good UV filtration.
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Replies: 10 / Views: 4,251 |
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Posted 11/12/2017 06:36 am
