If it were removed from the cardboard holder, it wouldnt be marked up like that unless it went back into circulation.
Yes, the mirror surface can be a good indicator, but bag marks are more definitive, as I have seen shiny, lustrous circulation strikes.
Here is a PL-66 dollar. There are no bag marks but sometimes there is a pebbly surface on the Queen's shoulder and/or the hair above the braid.
