A brilliant frosty coin that should have been designated FB. There are only a couple of tiny marks visible on the whole coin. What does it take for a 67?

Country:	United States
Denomination:	.10 Dollar
Date:	1951
Mint:	S
Grade:	66 FBPQ
Grading Service:	PCGS 5099.66/46309416
Metal:	Silver
Fine:	.900
AMW:	.0723
Item #:	0507-488