My guess would be that the PCGS site doesn't have a choice when listing a cent grade in MS. Like, if they are calling a cent MS, perhaps there's a required box they have to tick deciding BN, RB, or RD, even when it doesn't apply, like here. Just a hunch, but I bet it comes down to web design faults
A quick check of the PCGS certification database will show multiple examples of a Lincoln cent struck on a clad 10-cent planchet graded without any color designation. The example (with color reference) referred to here might simply be a data entry error (we all make mistakes from time to time) or might have been a short-lived label policy.
In any case, what's on the holder is most important IMO.
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