I obtained two large cents last month (1855 and 1857) and since then, one has taken on a dramatic metallic blue tone on the rim (pictured below). Edit: The blue cent was always darker than the pink cent beside it, in fact, those previous darker areas correspond exactly with the now-blue areas. Both were mounted identically in an old frame, from which I removed them. Both were handled identically in an attempt to remove some adhesive (soaking in water for a week, then a short stint in acetone). And both have been in a paper envelope since then (for about 1 week). I am shocked by the color change on the 47. I am guessing that the removal of the adhesive (or other substance) and the sudden environmental change allowed the "fresh" copper to react. But who knows? My main question is whether this unusual color would be considered artificial toning by grading companies?
I read this post initially about 2 hours ago and thought the same about how dramatic the change was. Interestingly just this moment I was browsing a Fb group I'm in where they were discussing a Fugio cent with some material on its surfaces. The people in this group are knowledgeable collectors and dealers. The comment that caught my eye "there are certain coin cleaners that leave a residue on the coins. Then, if you use acetone later, the combination will turn them purple." So... Working from there, you thought there had been a previous clean, possibly long ago, the residue reacted with the acetone and you now have your toned coin. Just a thought....
This is great information. Thanks! I found a blurry "before" picture from a few weeks ago, before removing the coin:
It could have been cleaned before and someone might have artificially could have toned it darker. I have had coins from Italy that someone had cleaned leaving them with an obvious strange red/orange color let me know that they were cleaned. This is my opinion. Wait for other options...
