Mg – magnesium – is a light, shiny metal with a silvery-white color. Pure magnesium is soft and fragile, but its alloys with aluminum, zinc, copper, and silicon are lightweight and strong. You can therefore find housings made of magnesium alloys in such devices as mobile phones, video cameras, and laptops. It is also used in the construction of automobile parts, aircraft parts, and even missiles. Magnesium can be found in many medicines. It is used as an anticonvulsant, laxative, sedative, cardiac, and antispasmodic. It is also used to regulate the acidity of gastric juices and to treat injuries and joints.