Redelf12, first, welcome to TreaureNet and its "What-Is-It" forum, the best place on the 'net for getting unknown objects CORRECLY identified. The Great Seal of the United States was adopted for use on US Army "general service" buttons in 1903. The first version of those Great Seal buttons (1902-1909) did not have a raised rim -- which yours has. They've had the rim from 1910 to the present. But your button's backmark (a maker's/dealer's mark) saying "R. Liebmann Mfg. Xo. Newark NJ" allows us to date your button from around 1916 through World War One and perhaps a bit later. The Rudolph Liebmann Manufacturing Company is listed as a seller of "metal and celluloid dress buttons" in the 1916 issue of "Style." Furthermore, from World War One through 1923, the Great Seal buttons were manufactured with a "black finish" so they wouldn't give away a hidden soldier's position. Your button shows traces of the "black finish" in the emblem's recessed areas, where it didn't wear off. So, your button could only have been made sometime between approximately 1916 and 1923. However, the manufacture of Army buttons dropped radically after the end of World War One, because there were so many "surplus" ones left over... so your button was most likely made between 1916 and 1918.
