Hello, JIMBUCKS, I see the slabbed coin. IMO, The coin shown is NOT getting is proper showing, The slab's marks are seen over the Grade of this Sweet Coin, Can you think about What I am seeing, I believe the coin, deserves More.... Best Wishes, ......
Frog. What appear to be marks are part of the toning. The toning appears much more mottled in the photos than in hand. Edit: Upon closer inspection it appears to be shallow "rays" that are part of the design. See the PCGS coinfacts page for pics of high grade examples that show these.
I have to agree with morgans dad. I have never done a screen grading of an example of this coin before, so it's going to be as the OP has suggested:- a guess. I also see what coinfrog sees, and I also see two obvious dings below Liberty's knee.
The 10 % copper has given this coin a somewhat of an old gold toning - quite a common characteristic of British Guineas of a century older than this coin.
MS-63.PCGS may? say a grade higher, or may? end up agreeing with coinfrog.