Controversial 1964 D 1 1

[J P M]

I was given this in my change tonight and I put it aside until I could get home an get a better look. It could be a High School experiment. It could be environmental damage. It is gunmetal black on both sides even the edge is the same color like some Black Beauty's. I thought I would post it and get some others thoughts. It is not in to bad a shape for a 64 D Like someone my have had it in a PVC holder there is some green on the coin so it is still worth a post in my opinion. 

[Lem E]

My guess would be environmental or heated up post mint at some point. 

[Oldhoopster]

I picked up this tip from a Fred Weinberg post a few years ago.  On improperly annealed planchets, the edges should not be the same color as the obv/rev.  They should have  an as struck appearance.  This is due to the friction and abrasion from the collar removing a very small amount of metal as the coin is ejected from the die

This makes some sense because the color change is due to the copper and/or nickel atoms on the surface reacting with the wrong atmosphere in the annealing furnace. This interaction is time dependent and wouldn't penetrate very far below the surface during the annealing process,  and be easily scrapped off by the collar during ejection.  Especially reeded coins.

 

[Just Bob]

Looks like it may have been in the ground for a while.

[J P M]

Thanks for the comments guys. I think it has been in the ground also and that is what is making it dark. In picture #4 you can see the overall very fine pitting in the field and letters making me think it was in black dirt for a long time.  As always nice to be able to post a oddity and get some feedback from others who have been collecting for a while before throwing it back in the wild.