1870-S

San Francisco struck only 50,000 dimes in 1870, a sharp drop from the 450,000 figure of 1869 and the lowest branch-mint dime delivery of the Reconstruction era. The reduction came from operational rather than economic pressure. Carson City had opened in February 1870 and was drawing Comstock silver bullion into its own assay and refining operations, the San Francisco coiner's bench was running on tight schedules against a heavier gold workload, and the branch produced a smaller business-strike dime run while it adjusted to the new three-mint arrangement that would define western federal silver coinage going forward. The 50,000-piece figure sits among the lowest non-Carson-City branch-mint dimes of the entire Seated series.

Strike on the 1870-S follows the branch-mint pattern with recurring softness on Liberty's head and the upper-obverse legend on later die states, while the central wreath reverse usually comes up reasonably full. The Legend obverse format opened in 1860 carries through unchanged, with UNITED STATES OF AMERICA replacing the thirteen stars Gobrecht's original design had carried, and the dime continued without an IN GOD WE TRUST motto because the planchet was too small to accept the ribbon banner that arrived on the larger silver denominations in 1866. Authentication rests on the Coinage Act of February 21, 1853 standards of 2.49 grams and 17.9 millimeters with a reeded edge, and on the S mintmark within the wreath on the reverse below the bow. Added-mintmark fakes built from Philadelphia 1870 base coins are the documented counterfeit vector, so the field around the mintmark should sit clean of tooling halos and the punch itself should match documented San Francisco mintmark styles. PCGS and NGC populations concentrate sharply in Good through Very Fine, with Extremely Fine and About Uncirculated examples genuinely scarce and Mint State survivors limited to a small handful.

The 1870-S is a Semi-Key whose 50,000-piece mintage drives a tighter survival distribution than the surrounding commercial S dimes of the period, and most collectors buy the issue certified in mid-circulated grades where the population still supports eye-appeal selection. Raw examples below the certified market call for careful weight, diameter, and mintmark checks. For the broader story of Gobrecht's design, the Civil War-era production, and the Carson City Mint, see the Seated Liberty Dime series history.