1875-S 20C, BM (Special Strike)

The Enigmatic 1875-S Branch Mint Proof Twenty-Cent Piece

The 1875-S Proof Liberty Seated Twenty-Cent Piece (#5307, BMCA #85307) is one of the more mysterious issues ever produced by the San Francisco Mint. Classified as a "Branch Mint Proof," records suggest that 12 specimens were struck, yet only six have been confirmed to exist today and two of these were not even attributed as Proofs until after 1975.

Speculation Regarding the Coin’s Historic Origins

In the 1970s, numismatic writer Don Taxay speculated that these coins were likely the very first Twenty-Cent Pieces struck at San Francisco, produced between June 1 and June 3, 1875, to commemorate the start of the new denomination’s production.

Technical Die Diagnostics

Unlike standard business strikes, the Branch Mint Proof 1875-S Twenty-Cent Pieces exhibit specific characteristics first detailed by R.B. White in the March 1974 issue of The Numismatist.

Key diagnostics include:

• Rims & Edges: Broad, flat rims measuring 0.9 mm wide, featuring square edges with partial wire extrusion.
• Surface Quality: Polished fields, clearly defined denticles, and sharp delineation of the central devices.
• Shield Polish: Three distinct horizontal die polish lines visible within the shield directly below the word LIBERTY.
• Lettering Breaks: Significant breaks in the left serifs of the letters "T" and "S" in the word CENTS.

While numismatist Walter Breen corroborated these findings, he noted a complicating factor: the dies used for these Proofs were later retained and utilized for regular business-strike production. This makes the "Proof" status dependent on the quality of the strike and the state of the surfaces, rather than the die variety alone.

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