Help identify 0

[katama69]

Help too identify 1989 Silver Dollar markings (4-4)

[Coinbuf]

That was not done at the mint, someone scratched or punched that into the coin after it left the mint.  No way to know what it means, perhaps part of a birthday date, or something that meant something to the person that did it.  The coin is just a bullion item so its value hasn't been significantly impaired although it may be harder to sell with those markings on it.

[Alex in PA.]

PMD.

[Greenstang]

It's called a counterstamp. Just ruined a a nice looking 1989 silver dollar.