That is interesting...no idea what could have caused it though especially since it is on both sides. Hard to tell from the photos but looks like some lamination issues by the rim on both sides near the bulge.
If the error is real, it's known as a "occluded gas bubble" - from improper metal mixture of the planchet strip early on in the minting process.
Usually, the 'bubble' is on one side; because it's on both sides, and the coin seems to have color and surface issues, it's possible it was heated to get this effect.
Usually these gas bubbles don't show on both sides of a thicker coin type like this Silver Dollar.....I'm somewhat suspicious of it.
Retired Collector & Dealer in Major Mint Error Coins & Currency since the 1960's.Co-Author of Whitman's "100 Greatest U.S. Mint Error Coins", and the Error Coin Encyclopedia, Vols., III & IV. Retired Authenticator for Major Mint Errors for PCGS. A 50+ Year PNG Member.A full-time numismatist since 1972, retired in 2022.
Comments
It's ALWAYS Peace Dollar Day.
K
"occluded gas bubble" - from improper
metal mixture of the planchet strip
early on in the minting process.
Usually, the 'bubble' is on one side;
because it's on both sides, and the
coin seems to have color and surface
issues, it's possible it was heated to
get this effect.
Usually these gas bubbles don't show
on both sides of a thicker coin type like
this Silver Dollar.....I'm somewhat suspicious
of it.
What ever happened to Peaceman?
He give up on us?