Q. David Bowers (edited and updated by Mike Sherman): Christian Gobrecht’s Liberty Seated motif, used on half dimes from 1837 through the end of the series in 1873, was struck in 1837 at the Philadelphia Mint and the following year at the New Orleans Mint, without obverse stars, thus isolating these two issues as a separate type. The obverse depicts the figure of Liberty seated on a rock, her left hand holding a liberty cap on a pole and her right hand holding a shield inscribed LIBERTY. The date is at the bottom border. The reverse consists of an open wreath tied with a ribbon, enclosing HALF DIME, with UNITED STATES OF AMERICA surrounding. Mintage figures reveal that 1,405,000 of the 1837 Philadelphia issue were produced while only 70,000 were made of the 1838-O.
Specimens are readily obtainable in grades from Good through Extremely Fine. The type collector will direct his attention to the 1837 for in every grade, the 1838-O is considerably more expensive. In AU and Uncirculated grade, the 1837 is available without too much difficulty, although top grade Uncirculated pieces can be tough. Uncirculated examples of the 1838-O are quite rare. The Liberty Seated design without stars on the obverse was used only on the half dimes and dimes, not on quarters of half dollars. In the dollar series, the no-stars motif appears only in pattern form in 1836.
-- Reprinted with permission from "United States Coins by Design Types - An Action Guide for the Collector and Investor" by Q. David Bowers