There are no true rarities in the lower grades (other than the 1892 micro-O), but three regular issues each have total mint state populations lower than that of the 1901-S quarter. Of the 73 regular issues, three are R6, 16 are R5, 10 are R4, 17 are R3, 15 are R2 and only 12 are R1. The micro-O, with only two coins certified, is R8 in mint state.
PCGS & NGC have certified a total of 9,636 Barber halves in mint state. This is about 2/3rds of the 15,315 Barber quarters and little more than half the 16,918 Barber dimes certified.
There were 5,152 mint state Barber halves certified in June 1991, when The Complete Guide to Barber Halves was published. This means approximately 550 mint state halves have been added to the population reports each year since then.
With the affluence that comes from the booming stock market and U.S. economy, mint state halves are currently enjoying unprecedented popularity. In practical terms, all halves that are rated R5 and above are often difficult to find. A nice mint state set can be assembled, but a little luck and patience will be required to do it in a reasonable amount of time.
Sources and/or recommended reading:
"The Complete Guide To Certified Barber Coinage" by David & John Feigenbaum
Designer: Charles E. Barber
Diameter: 30.6 millimeters
Silver - 90%
Copper - 10%
Weight: 12.5 grams
Mint marks: the mint mark appears as a small letter just below the eagle's tail on the reverse, as follows:
None = Philadelphia
O = New Orleans
S = San Francisco
D = Denver
Cherry Picker's List:
1892-O Micro O
1892-O A rare variety has a tiny mint mark that was normally used on Quarter Dollars.