The Little Rock Shield was first used in September, 1830.  Examples are known used until June, 1832. 

The Postmaster at the time was Dr. John T. Fulton, He was appointed in March, 1830 and served until October, 1831.  He was appointed again in 1835.

The Known examples of the Little Rock Shield are as follows.  Illustrations have been collected from auction catalogs, exhbits, and covers scanned directly.  The first usage, on September 9, 1830, is the "Type 1" with the shield contained in a square "box".  Either the results were not pleasing to Dr. Fulton, or the device broke.  After Sept 9, all usages are missing the upper square.  All strikes are in black except for the use on Sept 30, 1830 which was done with red ink.

Dates with an * in front of them can be clicked to see an image of the cover

Date        Rate    Destination                  Comment  
1830
*Sept 9    18.75    Saint Louis, MO.        "Type 1", the boxed version of the shield
Sept 30    25         Saint Louis, MO.         Only Shield struck in Red
*Oct   7    12.5     Washington, AR          To Chester Ashley, later Senator 
1831
*Feb 17    25        Basonville, MO.
*Feb 23      12.5     Batesville, AR.           Superb Strike
*Mar 10    50        Philadelphia, PA           Marked "Double", regular rate 25 cents  
May 5       25        New York, NY               One of three covers reported from May 5, 1831
*May 5     25        Techumseh, NY
*May5      25        Braintree, MA
*May 19   25        Cincinnati, OH
*June 13   FREE   Washington, DC
*Jul 7        25        Latarius, MS.               Considered the finest strike
*Jul 21                                                      Cut Square, not cover
Jul 28        50                                            Not seen since 1954. John A Fox Sale 3/5/1954
*Aug 25    FREE    Washington, DC          Only cover with two strikes of the Shield
*Sep 8      50+25  Fayetteville, NC.         Forwarded 25 due to Charlotte, NC
Sep 22      50        North Carolina
*Sep 29    50        Philadelphia, PA.
*Nov 24    FREE    Washington, DC.         To Senator Johnson of Iowa
*Dec 22    25         New York, NY.
1832
*Jan5        FREE    Washington, DC.         To the War Department
*Mar 22    25+10  Frankford, KY.              Forwarded 10 due to Long Ridge, KY.
*Apr 12     25        Chapel Hill, NC.
*May 10    25        Albany, NY.                   Last sold in 1956.  Seen in Smithsonian collection in the 80's
*May 10    25        Cincinnati, OH    
 *May 24    50        Philadelphia, PA.            "PAID" which is unusal.  To the Mint in Philadelphia
*Jun 21     25        New York, NY.               The latest reported usage

Updated 11/20/2009.