RRR-, Stefan Batory, Riga 1581 penny, GROSSVVS error (by two VVs), unlisted

It might have seemed that after Janusz Parchimowicz's specialized catalog, no undiscovered spectacular variety would appear anymore. Here we are faced with such an error, which is not due to some minor punctuation but a quite erroneous stamp, where VV was double-stamped, so that we have the wrong denomination GROSSVVS. The latest specialized catalog by J. Parchimovich, despite listing 21 varieties of the 1581 Riga penny, does not list the GROSSVVS variety (by two VVs). Onebid's largest archive, despite noting 143 pennies from this vintage, knows of no other pieces of this variety. We can add to this the Niemczyk Antiquarian Archive, which contains 33 pieces, where a coin of the GROSSVVS variety is also not to be found. A very nice deeply struck piece, NGC graded the details to AU (about uncirculated) condition - about mint. The lack of a numerical note, in our opinion, is a mistake, as NGC often for cylinder coins having convex lines erroneously qualifies them as cleaning. However, the note here is irrelevant anyway, as we are currently dealing with ONE KNOWN piece.