Because this is pocket change. This quarter definitely got baked. The Red is rusty looking corrosion.
A few more I have a couple plastic film canisters full of bicentennial quarters I filled up back in 76, the pic above reminded me of them.
What should I do with the green junk. Dip/clean the coins in baking sofa or something? Does it spread at all especially to other coins?
The deep whitish green is corrosion. I wouldn't dip them in anything other than acetone. maybe use a rose thorn to lightly pic at it. I think that MS70 might help? Never used it. @BadThad
Change looks ms74 to me lol other than a few nicks, scraps and wear. (yes, I know it only goes to 70)
Every morning I stop at a convenience store and my purchase is always $1.07 and I pay with bills, always getting .93 back in change. I save it all for this time of year and end up hand rolling a couple hundred dollars. I never paid much attention to all that coinage, but now, I think it will turn into a long, drawn out process.... Well , I could always check it out before it makes it to the jug.
I've recently started using plastic drink cups and mark them 1950 (and before), 1960, 1970, 80,90,2000 (and up) and sort them that way. But I don't know enough about pennies to know anything. I'll probably just keep the 1960s and earlier and recycle the rest. My eyes aren't as good as they used to be so I find this taking more time than I thought even for a little bit of change here and there. I also check the other change too and keep the older stuff.