A foil is a very thin sheet of metal, typically made by hammering or rolling.[1][2] Foils are most easily made with malleable metal, such as aluminium, copper,[3] tin, and gold. Foils usually bend under their own weight and can be torn easily.[2] For example, aluminium foil is usually about 1⁄1000 inch (0.025 mm), whereas gold (more malleable than aluminium) can be made into foil only a few atoms thick, called gold leaf. Extremely thin foil is called metal leaf. Leaf tears very easily and must be picked up with special brushes.[citation needed]