This mint stamp was issued by the U.S.P.S. on August 30, 1989, to pay tribute to those who carry America's mail to over 100 million delivery points. The stamp features letter carrier caricatures.

Issued to celebrate photography, one of the most popular hobbies, this mint stamp features a camera, fritters, and other photo equipment. The first day of issue was June 26, 1978. The perfect stamp for the photographer.

This mint stamp, known as the Chemistry Centenary issue, was issued on April 6, 1976 to commemorate the 100th anniversary of the American Chemical Society (ACS). The design features various laboratory flasks and a separatory funnel with a "computer tape" background.

Issued on October 6, 1975, the United States paid tribute to the importance of banking and commerce in the nation's development with this attached pair of mint stamps. The design features gold coins and currency engraving.

This attractively designed stamp paid tribute to America's pharmacists and their contribution to health care. Included in the design is a bowl of hygeia and a mortar and pestle. The first day of issue was November 10, 1972.

The 75th anniversary of the American Osteopathic Association is commemorated by this mint stamp. The AOA was established by Dr. Andrew Still. The first day of issue for this stamp was October 9, 1972.

The 75th anniversary of the Parent-Teachers Association (P.T.A.) was commemorated by this Sept. 15, 1972 issue. The P.T.A. is dedicated to improving the education process. The stamps features a blackboard with chalk writing.

The United States issued this mint stamp on May 17, 1968, to publicize the work of law enforcement officers as protectors and friends of the people. The design features a policeman and young friend.

This mint stamp, issued by the United States on September 11, 1964, commemorates the 50th anniversary of the founding of the world-renown mayo Clinic in Rochester, MN. The stamp also pays tribute to William J. Mayo and his brother Charles H. Mayo (doctors and surgeons).

This October 26, 1963 issue commemorated the 100th anniversary of city mail delivery. Before 1863, letter recipients would generally pick up their mail at the post office (you may have seen old letters with an address listing only a name, town, and state- no address was needed). The stamp design features artwork from Norman Rockwell: a postman flanked by a boy and dog.