Re: Gage Block Minumim Grade.
What is the minimum grade a gage block should be to calibrate micrometers and Digital caliper verniers?
Micrometer, Resolution 0.00005 Accuracy +/-.00005
Vernier. Resolution .0005 Accuracy +/-.0005
Generally, you want to maintain a 4:1 ratio for your master and gage being calibrated. You should reference the grades in ASME B89.1.9. if you don't have the standard, the grade specs are listed in Starrett and Mitutoyo catalogs (and the like).
Provided you are talking about 0-1" mics, you want to have gage blocks accurate to at least 12.5 millionths (0.0000125"), which would be ASME Grade AS1. This isn't considering any measurement uncertainty in the process. If it were me, I'd go one more grade better ASME Grade 0.
The AS-1 grade would be sufficient for the vernier caliper.