'49 Wheat with silver/nickle inclusions?

[riff]

These are not paint, and they seem to be embedded totally flush. Does this happen often?

[jallengomez]

It can't be ruled out, but on a coin that circulated one could also speculate in other directions. I've pulled some intrinsic metal inclusions out of uncirculated rolls, but the inclusions have always been linear instead of round.

[riff]

so the tiny one above the 9 popped out and left a little divot when i used a toothpick to make sure it wasn't paint or solder. it was taken out of circulation in the late '60's, early '70's according to the guy i got the album it came in from, but im surprised they didn't fall out before then.

[jcuve]

I agree, with it circulated it could also be environmental - and that all the intrinsic inclusion examples I too have seen were more like streaks within the copper. I wouldn't rule out it being struck through something that was embedded. Maybe wait for Mike D.

[GrumpyEd]

It can't be ruled out, but on a coin that circulated one could also speculate in other directions. I've pulled some intrinsic metal inclusions out of uncirculated rolls, but the inclusions have always been linear instead of round.

That's been my experience as well. Often on the wartime composition copper cents (shell case) I'll see linear streaks of silver color.
I wouldn't rule out something causing spots on a circulated coin or tiny inclusions showing up because different metals react differently to whatever the coin is exposed to.