Alexander Calder was an American sculptor and artist known for inventing mobile sculptures that incorporated hanging or moving parts. Some of his most famous works mentioned in the document include La Spirale from 1958, Lobster Trap & Fish Tail from 1939 made of painted steel wire and aluminum, and Mercury Fountain featuring actual mercury from the 1937 World's Fair in Paris. The document also lists several other abstract metal sculptures Calder created between 1926-1973 such as Red Panel, Big Bird, Teodelapio, and Flamingo made using materials like sheet metal, wire, and paint.