Has anyone seen a worse coin given a MS 65? Lately, so many MS 64-65-66 are ugly, hideous coins. Please post your hideous coins here...
IDK. I could see this being slabbed when it looked nicer, and either environment of some substance someone put on it and not recognized when slabbed has turned. Kid of like the putty gold coins PCGS issued lawsuits over the submitters on a few years ago. They looked good when PCGS saw them, but the putty became evident later and gave PCGS a black eye.
I suggest storing your coins, even slabs, in the presence of "sacrificial silver", as well as stored in low humidity, no sulfur environment. Get fresh silver and throw in there every once in a while. Look at the loose silver to give you an idea of how good your environment is. Intercepts can be good, but they become used up. Best to concentrate on your environment and use pieces of fresh silver as your canary in the coal mine. Dirty secret with toned coins is once they are toned they are subject to toning more. A pretty toned coin can quickly turn ugly if stored improperly. Toning is not a stable attribute like date, mintmark, and grade is if you are not careful.
I won't disagree, but the paper label is less isolated in these slabs. Hence, a stronger and quicker reaction often does occur in my observation.
I would think you want the sacrificial anode to be something more reactive than what you are trying to protect. So fresh copper or even scratched zincolns to expose the zinc would be better than just another piece of silver, no?
It may have been dipped before it was slabbed and not properly rinsed. Overtime the residue has killed the coin. It didn't look that bad when it went into the slab. I can tell you that for sure. The worst case I ever saw were some Proof Indian cents that were slabbed. The butcher who cleaned them seemed to leave all the chemical on them. The coins literally dissolved in the holders.
There are a lot of idiots on eBay cleaning coins, and this one cleans indian cents; mikesmountainvalues