Green Spots On A 1968 (Or 69) Kennedy Half What Is Is Bad Clad Job.

A soak in acetone can't hurt

That bright green gooey look is pretty unmistakable as PVC damage. It can be remedied but not really worth it on this coin. https://www.ngccoin.com/news/articl...onservation/
If you see anything like this being marketed as a "clad error", as your title implies, don't fall for it.

It's damage from PVC for sure, seen it many times. Soak the coin in acetone and gently use a q-tip to remove it while under fluid. It should come right off. VC will also easily remove this type of residue/corrosion.

Ok I'll soak it,as for Verdigris I never had much experience with it so does green Verdigris happen on any coins other than copper ? I read silver clad coins get it bad but not so much the nickel clad coins,just trying to learn.

No not this coin I'm sure now it's PCV but just Verdigris in general,I read that all coins with copper can get it even gold coins but it's rare in gold and it's quite odd for a silver coin to get it but was wondering about the clads like silver clads and the nickel clads,do they get too too.

Hi,yes I agree with you,and your coins have been in the ground so for a coin in a collection with really only air and no water contact I guess it is a not common thing,OK I learned something.

This is actually fairly common for all silver that's not pure, not just coins. What you're seeing is the impurities in the silver alloy, namely copper, oxidizing due to the environment. For reference, this is the same color as the Statue of Liberty (made of copper exterior), which originally was not that color when France first gifted it to us. The more copper in the silver, the more pronounced this will be. You're going to see this in 90% silver, sterling silver (92.5%), (European) continental silver (80% or some other permutation), etc. The only place where you're NOT going to see this is 99.9% pure silver.

This green oxidization is not the same as tarnish for silver, which is a noble metal, meaning that it does not interact with most elements. It does, however, interact with sulfur and compounds containing sulfur, which causes the blackish tarnish. When coin collectors say "toning," they're basically referring to silver tarnish. I always get a chuckle out of that, because "toning" is actually very common for all items made out of silver, not just coins. It appears this tarnish/toning is only desirable for coins for some reason. That said, I almost never clean my tarnished silver items, unless it's for experimentation.

Hope this helps. Cheers!

I have to agree with previous posters that this is PVC damage. I doubt this will come off but you can try an acetone soak and then dip it into MS-70. At least that will remove the PVC so it won't get any worse. If this were just the scuz aka-seltzer look toning that a 50c1968-D gets from being a mint set coin that usually comes right off with MS-70. PVC is a different story in that you have to catch it early.