1875-S BF-1 Twenty Cent old ANACS AU55, the Proof Dies

According to research by our friends Lane Brunner and John Frost (their book, Double Dimes, The United States Twenty-cent Piece, was published in 2014), this scarce die variety was struck by the same die pair that produced the very rare Branch Mint Proof 1875-S 20c coins, less than 10 of which are known. This coin is mildly PL beneath the pretty, antique golden and iridescent toning, but was clearly not issued as a proof. It is lovely and very appealing though!