Ron Guth:
The 1833 Half Eagle is a very rare coin, due in part to a low initial mintage but due mostly to the destruction of many examples whenever the value of the gold in the coin exceeded its face value. Both Small Date and Large Date varieties are known for this year. Apart from their size difference, the two varieties are most easily attributed simply by looking at the 8 of the date. On the Small Date, the 8 is a "script" 8 with a diagonal center bar. On the Large Date, the 8 is a "block" 8 with a horizontal center bar. Based on the PCGS Population Report, the Small Date is approximately twice as rare as the Large Date. All except one of the examples certified by PCGS as of May 2011 are Mint State, ranging in grade from MS-61 to a gem MS-65. This indicates that most of the surviving examples are coins that were set aside by collectors.
David Akers (1975/88):
Although the 1833 is a very rare coin, particularly in gem condition, it is possibly the commonest coin of this type unless one combines the varieties of 1830 or 1834. There are two different sized dates for 1833 but the differences are rather slight and past cataloguers have generally made no distinction between the date sizes over the years. Almost all known examples are AU or Unc as the auction data clearly shows.