The Smithsonian Mace was commissioned in 1964 by the Institution in anticipation of the celebration of the bicentennial of the birth of the Smithsonian’s benefactor and namesake, James Smithson. The 47-inch mace was unveiled Sept. 17, 1965, a gift from friends of the Smithsonian; it is constructed of gold and silver and encrusted with diamonds, rubies and polished Smithsonite, a mineral identified by James Smithson and named for him posthumously in 1832.