A Congressional Silver Medal is an award bestowed by the United States Congress. They have been made in either non-portable (not designed to be worn) or decoration (designed to be worn) form.
Congress has been authorizing gold medals since George Washington received the first one in 1776. Occasionally Congress will authorize a silver medal in conjunction with the higher award.
In 1976, President Gerald Ford presented, on behalf of Congress, a silver medal "equivalent to a noncombat Medal of Honor" to Brigadier General Charles "Chuck" Yeager, "for contributing immeasurably to aerospace science by risking his life in piloting the XS-1 research airplane faster than the speed of sound on October 14, 1947." This apparently unique award—equivalent to a noncombat Medal of Honor—is sometimes referred to as a Special Congressional Silver Medal.