1976-D Nickel Cud? Die Crack?

I have just recently started searching nickel bank rolls, so I'm still not up to speed on them. I have noticed several coins to have what look like a bad alloy mix, similar to what a lam would show but at the rims. I thought that was what I saw here at first but think we need some very clear closeups. This looks similar to a radical mad die clash I found on a Lincoln Cent. I may be out in left field though....

For sure not a Cud.
John1

(Ever wonder what goes through coop's brain when looking at a coin?)

Looks like an aging die. The reason the fields are so flat is that it recently when through a polishing from Feeder Finger Damage. (Note the brow by the nose) There are some contact marks on the rim on that area, but why are the devices so close to the rim? (Looking up examples on PCGS to see if the master hub was swelling outwards. Edited image below)

The design shouldn't be that close on the OP's coin, so the aging of the diethat struck this coin is proved. But the contact marks may have altered that area on the coin. (Took a hits during circulation)

If this were a Cud it would rise above the whole area.

Note the image on the right? The die edge slivered off the die, leaving a void on the die. When the coin was struck the void was filled, thus it is just slightly over the top of the edge of the coin. This is not going on with the OP's coin. Looks more like moved metal on that area. Note even a chip. Just a spender coin that is damaged slightly. It will probably be continued to be circulated for many more years.

(That is what is going on, in coop's brain)

(Ever wonder what goes through coop's brain when looking at a coin?)

No. He has all the material he needs to figure it out. Not to mention he is well versed. LOL