Are all proof Mercury Dimes FSB by default?

Longacre

I noticed that a lot of proof Mercury dimes are not listed as FSB. Is this because a proof is FSB by default, or is it FSB a designation used just for MS or circulated pieces, in order to distinguish them from others that don't have FSB?

mercurydimeguy

FB is a business strike designation

XpipedreamR

I believe that FSB is just used for regular strikes by convention. I have seen a number of proof Mercury dimes, though, that are surprisingly weakly struck in the bands, and would not qualify for FSB if that that designation were available.

coinguy1

<< <i>I believe that FSB is just used for regular strikes by convention. I have seen a number of proof Mercury dimes, though, that are surprisingly weakly struck in the bands, and would not qualify for FSB if that that designation were available. >>

I agree.

Deadhorse

Sort of like FBL on the Frankies.

You'd think they should all be, but it doesn't work that way in reality.