Q. David Bowers (edited and updated by Mike Sherman): The regular Liberty Seated design, which had been in use since 1839 was modified in 1866 by the addition of IN GOD WE TRUST to the reverse. The motto appears on a scroll or ribbon above the eagle. A similar change was effected in the quarter and dollar denominations. Production was continuous at the Philadelphia mint from 1866 onward, though quantities struck after 1878 were sharply curtailed due to the production of Morgan Dollars. Business strikes were also made at San Francisco and Carson City, with several of the Carson City issues, particularly those made in the early 1870s, being rare today. The series boasts a major rarity as well, with the 1878-S costing mid-five figures, even in lower circulated grades. Certain half dollars of 1873 and all of 1874 again have arrows at the date, and are a separate type discussed in the next listing.
The “common” dates in the series are generally the Philadelphia and San Francisco issues of 1875-1877, and collectors should find them relatively easy to obtain in any grade from Good through MS-65 provided they’re willing to pay the price. Superb MS-66 and MS-67 examples, while around, are both costly and scarce. Proofs exist in proportion to their original mintages.
-- Reprinted with permission from "United States Coins by Design Types - An Action Guide for the Collector and Investor" by Q. David Bowers