Ron Guth: The two most obvious differences on 1804 Half Cents relate to the 4 of the date. On some coins the horizontal crossbar of the 4 ends with a vertical crosslet; on others the 4 has no crosslet. The Crosslet 4 is slightly lesscommon than the Plain 4.
The Crosslet 4 obverse is combined with two different reverse types: Stems at the base of the wreath and No Stems at the base of the wreath.
Only one die variety (Cohen 12) qualifies as the Crosslet 4, No Stems variety.
Uncirculated examples of the 1804 Crosslet 4, No Stems Half Cent are scarce, but can be found in grades up to MS65 in both Brown and Red-Brown formats.