Half dollar error or PMD?

[FormerTeller]

Found an odd looking bicentennial half today while roll hunting. It has a uniform pebbly texture covering both sides of the coin, severe enough to render “ 200 years of freedom” and “ E PLURIBUS UNUM” almost illegible. I would’ve thought it was a strike through grease or similar error, except there also appears to be a bulge on both sides of the coin, just to the right of Kennedy’s head. This leads me to believe it is some form of post-mint damage, fire or something that was cleaned up. Pictures below.

Any thoughts?

 

[GopherDaGold]

Over-tumbled is my guess. I have an Ike dollar that looks similar.

 

[cudamark]

Beach coin

 

[Mackaydon]

As cudamark said; beach coin.
Don....

 

[FormerTeller]

Thanks for the responses.

 

[ILikeMoney]

Looks like it was exposed to acid.

 

[unclemac]

that is called "shipwreck effect"

 

[Dozer D]

Looks almost like a shot blast effect.

 

[PullTabPete]

Electrolysis test coin

 

[nomad 11]

Found an odd looking bicentennial half today while roll hunting. It has a uniform pebbly texture covering both sides of the coin, severe enough to render “ 200 years of freedom” and “ E PLURIBUS UNUM” almost illegible. I would’ve thought it was a strike through grease or similar error, except there also appears to be a bulge on both sides of the coin, just to the right of Kennedy’s head. This leads me to believe it is some form of post-mint damage, fire or something that was cleaned up. Pictures below.

Any thoughts?

View attachment 1807100View attachment 1807101

thats the effect i would get from letting them sit in ketchup too long