I don't mean to be presumptive, but are these coins you have purchased according to the grade on the label, or.....?
I don't think that coin is close to a 66. Without better pictures and a photo of the reverse, it's impossible to say what it might grade. I believe the coins was dipped at some point and not properly rinsed.
Agree with everyone. . . This is not a 66. Based on the pictures, it appears that the lady has been dinged a few times. Nice coin though.
Hallmark was a respected name in the early days as I recall. Like all the grade/slabbers had ups and downs while in existence. If I had a Hallmark slab Id consult a trusted local expert to see if it should be left in that slab or sent off for a more appropriate grade. It may actually look better or worse than your pic as sometimes we end up looking at defects in the plastic rather than the coin. My Peace dollars always look cherry until I see a nice one like Dunk's 65.
Yes it was, but that was not the same company as this Hallmark. (There have actually been three different Hallmark grading services.)
Looks like a 63 with water spots on it or was dipped and not properly rinsed as someone previous said
To me, it's hard to say from that picture what's on the coin and what's on the slab. Are you going to send it to PCGS to see if it will cross over?