Ron Guth:
In 1859, the New Orleans Mint produced far fewer Half Dimes than in the previous year, dropping the mintage from 1,660,000 coins to a mere 560,000. However, the PCGS Population Report shows the 1859-O to be only twice as rare as the 1858-O, suggesting that collectors may have set aside more of the 1859-O's since this was the last year that New Orleans would produce No Stars Half Dimes.
In general, this date shows the poor strike qualities typical of New Orleans Mint products. Often, the stars are weak; more often, the denticles are weak. Nonetheless, a well-struck 1859-O shows up occasionally and such coins should command a nice premium.
The best example known of this date is a single PCGS MS66+ (illustrated above)