I have a 2013 1/10 oz gold Panda in a PCGS holder that has darkened to a light copper color. Has anyone else experienced this?
I have an MS70 gold eagle that is doing it. But I think you'll have better luck in the coin forum on this.
Yes, it's common for gold to develop red spots or reddish toning, and Pandas are prone to tone. I have had gold Panda's with red spots. Coins can tone in TPG holders as well. Here is an old thread with discussion on the topic. Some of my images are still linked in that thread which you can see the red spots on a Panda coin: https://www.cointalk.com/threads/cause-of-red-spots-on-gold-coins.126202/
