magnesium processing | Techniques Methods | Britannica
Magnesium (Mg) is a silvery white metal that is similar in appearance to aluminum but weighs onethird less. With a density of only grams per cubic centimetre, it is the lightest structural metal known. It has a hexagonal closepacked (hcp) crystalline structure, so that, like most metals of this structure, it lacks ductility when worked at lower temperatures.