Expectations of a granite surface plate ...

[arvidj]

I have in imported granite surface plate.

Sort of a two part question ...

Should there be an expectation that both primary sides (the 9 x 12 sides, not the 3 x 9 and 3 x 12 "sides" and "ends") will be flat? In other words there is not 'top' or 'bottom' to the plate.

Should there be an expectation that both primary sides be parallel?

Is so, any suggestions on how to check to see if my plate meets those expectations? I am guessing that a simple "measure it with a micrometer" might address the second one, but the first one has me stumped.

Thanks,
Arvid