Alexander Calder applied red paint to many of his works made of this material, which he suspended from wires to form mobiles.
The artist of a sculpture made of this material filed a lawsuit against its removal, saying that removing it would destroy it. Richard Serra's Tilted Arc is made of this material, which Claes Oldenberg used for a sculpture of a giant tube of lipstick on caterpillar tracks. Jeff Koons used this material to create large sculptures based on balloon animals. Alexander Calder applied red paint to many of his works made of this material, which he suspended from wires to form mobiles. Anish Kapoor used this material for Cloud Gate, commonly known as Chicago's "The Bean." For 10 points, name this class of material often used in sculptural art, which includes aluminum and steel.
The artist of a sculpture made of this material filed a lawsuit against its removal, saying that removing it would destroy it.
metal [or steel; or aluminum]