I took a little break from hardcore 'coining' as life was just taking so much time. Anyway, today I opened my pres. dollar book (all coins in cardboard 2x2s) and was surprised to find *very* ugly dollars!! I understand toning, etc. however what used to be very bright, vibrant coins changed to DULL, grayish pieces.... What are these coins clad in? Disappointing... I know no one likes 'em but I thought they were pretty cool looking, esp. for the kids and learning their presidents!
The coins are 88.5% Copper, 6% Zinc, 3.5% Manganese and 2% Nickel. I expect that copper is the culprit! PEET-CHURES are definitely needed here.
At this point we don't know if this is toning or PVC from the wrong kind of 2x2's or the book pages. I would not expect a normal toning process to turn a coin "dull and grayish;" one would think at least a little bit of color should be involved. No chance at a real opinion/advice until we see the problem, though.
I think so, I believe the silver war nickels have manganese in them as well, and boy are most of those ugly!
Cardboard 2x2's don't cause toning by themselves. The folder/album might be to blame but my guess is that there's humidity involved. Manganese will tarnish and moisture will accelerate it.
It's the manganese that oxidizes and turns gray. I let an open roll sit on my counter in some proximity to the plastic bag with my gold testing acids in it. Just a week or so was required and they were totally ruined.
Storage is a big part of it. These dollars don't like humidity, temperature changes or holder changes. They seem to tone really fast.
This seems to happen with all of the so-called "golden dollars" when exposed to air for some time. They apparently need encasing in storage that at least limits exposure. Back when the 1st year Presidential coins came out, I put a wad of them into a simple coin tube, then put that tube inside a sealed box. I opened them up the other day and was happy to find them still shiny and golden, unlike just about every single one I've ever seen in circulation. When I was at the Winnipeg mint earlier this year I asked the tour guide about this discoloring (it also happens to their golden Loonies) and she claimed that they had solved the problem with the latest issues (I unfortunately don't remember her explanation, but the Krause guide shows that Loonies since 2012 are made of brass plated steel, prior to that they were made of aureate-bronze plated nickel). I brought back some shiny 2015 Loonies with me, but I'd rather not dull their blazing luster, so I've kept them encased like the Presidential coins.
I'm sorry guys still rusty from the layoff, I'll post some pics when I get home tomorrow... hope all had a great Thanksgiving! I think this is somewhat a testament to how "exposed" coins are in a 2x2... my PCGS pres. dollars proved to be unchanged. BTW all my coins are in my den, 20-45% humidity.