10.0 Mint
9.8 Near Mint/Mint
9.6 Near Mint +
9.4 Near Mint
9.2 Near Mint -
9.0 Very Fine/Near Mint
8.5 Very Fine +
8.0 Very Fine 
7.5 Very Fine - 
7.0 Fine/Very Fine 
6.5 Fine + 
6.0 Fine 
5.5 Fine - 
5.0 Very Good/Fine 
4.5 Very Good + 
4.0 Very Good 
3.5 Very Good - 
3.0 Good/Very Good 
2.5 Good + 
2.0 Good 
1.8 Good - 
1.5 Fair/Good 
1.0 Fair
.5 Poor 

Example grade certification