Could be a D mint mark with a small die chip or even circulation wear that affected it. I will say circulation wear.
It’s either a filled mm or circulation damage. The inner part of the mm is very small and it isn’t uncommon for it to chip off the die. Technically, it would be a die chip. It does not add any additional value. Sometimes, a hit on the mm or normal wear and tear can also push the metal around make it look like a filled mm. Hope this helps.
Nothing special 1979-D – Damage or Machine doubling (can’t tell from the pic) Mercury Dime – Damage – BTW: AW are the designers initials, not the mm 1989-D – Answered in your previous thread 1968-D – Looks Normal 1980-D? - Damage
You should learn to expect that coins that have been in circulation for any length of time will begin to show wear in all sorts of places. Chris
Of the last five you showed Circulation damage circulation damage to the 0 and the AW monogram zinc rot setting in. There is also some die deterioration on the 9. pretty much normal circulation damage.
