Liberty Seated dimes present the collector with the opportunity to study numerous mintmark sizes and styles. Identifying the mintmark size is the first step in differentiating reverse dies within a date. Both the New Orleans and San Francisco mints produced dimes with varying mintmark sizes while the Carson City mint only used one mintmark size and style.

Both Ahwash (1981) and Greer (1991) have documented the major mintmark sizes and style variations across the seated dime series. The author will adhere to the existing nomenclature that describes variations in mintmark sizes and styles to provide consistency between reference books. It can be expected that differences in mintmark size will be seen between reverse dies for a given date due to variations in die preparation. A deep or shallow penetration of the working die by the mintmark punch can cause minor changes in the size and appearance of each mintmark. Furthermore, the mintmarks of seated dimes are affected by circulation wear. Seated dimes in grades between Good to Fine can be expected to show a flattening of the mintmark as the top surfaces are worn away versus those dimes grading from Extra Fine through Mint State.

Continued inspection of mintmark, through the use of digital scanners and imaging processing software, has revealed additional and undocumented mintmark styles within a previously discussed mintmark size. Several dates have been identified with these different mintmark punch styles for the same mintmark size. In order to present a complete review of both old and new mintmark informations across the seated dimes series, a pictorial display of each date's mintmark is presented with subtitles defining size, style and size. The New Orleans mint will be reviewed first followed by the San Francisco reverses and then Carson City.

1838 and 1839 New Orleans

1840 New Orleans

Prior research has shown the 1840 No Drapery dimes to have three mintmarks sizes, large, medium and small. A fourth mintmark style and size (Small O 0.9mm) is now added to the population. This mintmark appears to be similar to the Small O of 1839 so it is described as a Small O.

1841 New Orleans

The 1841 Large O is from a left over 1840 reverse die re-used to strike initial examples of New Orleans coinage early in 1841.

1842 and 1843 New Orleans

1845 and 1849 New Orleans

1850 New Orleans

1851, 1852 and 1853 New Orleans

1854 and 1856 New Orleans

1857 and 1858 New Orleans

1859, 1860 and 1891 New Orleans

The 1860 below wreath mintmark measures only 0.7mm and could be considered to be a micro O.

1856, 1858, 1859 and 1860 San Francisco

1861, 1862, 1863 and 1864 San Francisco

1865 and 1866 San Francisco

1865 and 1866 seated dimes are seen with both the Small Thin S and a Small Weak S. Both mintmarks could have originated from the same punch, however they are listed separately to aid collectors with the identification of the different reverses dies of these two dates.

1867, 1868 and 1869 San Francisco

A Small Weak S has been identified for an 1869 reverse die.

1870, 1871 and 1872 San Francisco

The Small Weak S is again found on all 1870 and 1871 reverse dies. During 1872, the first usage of the Small Block S is seen.

1873 and 1874 San Francisco

1873 and 1874 seated dimes can be located with four different mintmark styles. Both the Small Block S and Small Thin S are found on 1873 examples while the first appearance of the Micro S is made on 1874 dimes.

1875 San Francisco

A new Medium S punch was employed for all 1875 In Wreath reverse dies, while Below Wreath dimes can be found with the Small Block S, the Micro S and rarely with the Small Filled S. The 1875 Micro S comes with either a filled or unfilled mintmark, with the unfilled Micro S being extremely rare. The Small Filled S has been listed by Breen as a "Tall Narrow S" within his Encyclopedia of U.S. and Colonial Coins.

1876 and 1877 San Francisco

For 1876 and 1877 seated dimes, a Small Filled S measuring 0.9mm is presented. Most likely, this filled S mintmark originated from the same punch as the Small Block S. However, the Small Filled S has been listed by Breen as a "Taller narrow S" within his Encyclopedia of U.S. and Colonial Coins and is therefore presented here to facilitate easier identification.

1884, 1885, 1886 and 1887 San Francisco

1888 and 1889 San Francisco

1890 and 1891 San Francisco

1871, 1872, 1873 and 1874 Carson City

The same reverse was used to strike Carson City dimes dated 1871 through 1874.

1875 and 1876 Carson City

1877 and 1878 Carson City