Hi Folks went to a munismatics faire sunday - apart from finding out how little I know, I saw a couple of what looked like NGC slabbed coins with a PL 61 grade. Now I'm familiar with the 1-70 grade and why proof coins have a PR rating, but a PL rating is new to me. Also, is PR rating only between 60-70? Would you get a PR51 coin, or does it just fall into the AU XF etc grade? I hope that makes some kind of sense... Thanks!