Can a silver coin in a capsule turn color or tarnish? Customer Service person told me that this is normal! Really! So why bother buying silver coin in a capsule?
Though not air tight, the capsules do offer a good degree of protection for the coins. For example, it allows them to be easily handled without fear of getting fingerprints on them. That said, toning or the development of colouring on a coin in one of the Mint's capsules can occur and does - it's not uncommon.
It's a question/discussion topic that has come up a few times here on CCF. I believe the colouring is due to a reaction within the coating the Mint applies to its coins - under certain conditions (e.g., prolonged light exposure, heat, humidity), some coins develop a golden tone due to this reaction.
Here are some previous discussion if you're interested:
- Group of Seven - Golden Coin?
- Proof Set Error? 2016 150th Anniversary of Transatlantic Cable
- Something Odd About Some R C M Coins
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