1964 D Die Clash Or ?

Impossible to say for sure without clear photos - appears to be damaged.

It looks like damage on both sides. It has the appearance of being smashed between two other cents. The only way that could be a doubled strike on the reverse side, is if it was also rotated and the secondary image is raised from the coin's surface. On your coin, the second image looks incuse, not raised. For the same damage to show on the other side, including on the rim part of the coin, would be something that wouldn't happen during the minting process, so it had to happen post strike, which makes it damage.

A die clash only affects the fields. The fields are the outside part of the die. The devices, bust and building is deep into the die. When they clash together without a planchet between them, only the outlines of the deeper devices are affected on the opposite die.
When a coin is smashed with a blow to the coin or in a vice, the raised devices transfer to the coins. So when you see the tops of the devices, bust and building damaged, it is the coin that is damaged. It wasn't struck that way. Here is the strongest die clash I have images to show you.








Note only the outlines of the devices are transferred to the coin and the deeper parts of the bust and building are not affected, because they never touch. also a clash mark is slightly raised. Damage is always incuse on the coin.

Ok thanks.

When I get home from vaycay, I'll actually get to see it.
If I have anymore questions I'll make a new post with wayyy better pics.

Thanks to all.