Grading records.

Well, sealed says it all. You cannot say mint without examining/playing the disc and that requires breaking the seal.

But if you break the seal, then you cannot any longer call it mint. I thought the "Goldmine" definition of mint is unplayed/unopened. It then becomes excellent, or for some people mint-.

You can grade jacket as not mint. or Mint- with comments on cut-out.
You needn't grade the sealed record.
I had an exception when I got the record from the sealed jacket with scratches and was greatly pissed with large question mark on my face when I came back to the counter but they let me exchange for the good one in such odddd case...