I posted about this coin when I found it several years ago at a local bank (thread:
http://goccf.com/t/79068&SearchTerms=1983-S,Half). It had suffered scuffs and abrasions from handling before I rescued it. ANACS certified it as a genuine rotated die error coin with a grade of PR-62 DCAM. Several posters commented that the coin might benefit from conservation so I recently sent it in to NGC/NCS for that service. Here are before and after pictures.
In ANACS slab, before conservation:


In NGC slab, after conservation:




I think the conservation really enhanced the cameo and restored some of the clear mirror surface. Abrasions seem less evident. NGC called the result PF-61 UCAM which seems accurate. ANACS was generous with their original grade but now it really deserved the ultra cameo designation.
This is the first time I've had any coin conserved and I'm impressed. What do you folks think?