1967 and 1968 Lincoln d penny sorry dont know that much but i know people are always talking about errors one has numbers slightly smushed looking other the L is not fully there still have a lot more to go through
The 68-d is kind of blurry, but my initial thought is that they are nothing special. Waiting for the experts to chime in...
Just remember US coinage *was* used and *is still* used for actually commerce. Thus the details get worn down over use. I still find 60s, 50s and 40s cents in change/circulation quite regularly.