How Should UNC €2 Commemorative Coins be Stored? Can they be cleaned?

[mdmckenna]

Hello,
I was wondering if anyone is able to tell me the best way to store UNC €2 CC. I have mine I these coin trays but I have noticed a deterioration in the coins, they have lost their shine, especially on the underside where they are in contact with the tray.

https://www.primus-muenzen.com/muenzbox ... ro-muenzen

Is it normal this loss of lustre? And is it possible to restore the coins and protect them some other way?

I have seem this. Has anyone tried it?

https://www.leuchtturm.com/coin-cleanin ... 00-ml.html

Hopefully someone will be able to help as it's a bit frustrating seeing the deterioration in the coins, especially as I have been very careful handling them, gloves, etc.

Many thanks.

[Yuri]

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