What type of error is this. (1969 Proof Quarter)

[1996]

Found this quarter in a 1969 proof set i busted. I tried out taking pictures through my loupe with my camera, and i think it turned out pretty good. What do you think?
I know this is an error, I'm just not sure what type, or how common it is. The rim is splotchy all the way around (on the outside), and the back is normal.
IDK, any help?

 

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[utah hunter]

The nickle layer over the copper was thin on the edges and the copper shows on the rim. Not sure the collectors value on a proof coin, I have found many on normal coin strikes.

 

[1996]

yeah, it looks trippy. is there a term for it?