Exceptional coin for this series; museum quality.
Excellent luster and and toning. I will go so far as to not call it a 'patina'.
With British coins that have no wear, I find it easier to go into the Sheldon grading system, because the numbering system is a little more defined and precise.
There may be some tiny nicks under the toning, but if they exist I can't see them in the pictures, so I will assume there aren't any, but a couple of tiny rim nicks. Slight staining on the '11' (1 o'clock obverse).
MS63.