Mag

Mag, short for magnesium, is the chemical element with symbol Mg and atomic number 12. It is the lightest structural metal in common use and an alkaline earth metal with a silvery-white appearance. It is highly reactive and tarnishes in air; it burns with a bright white flame when ignited, especially in powder form.

In nature, magnesium occurs mainly in minerals such as magnesite and dolomite, and it is the eighth-most abundant element by weight in the Earth's crust. Commercial production is primarily by electrolysis of magnesium chloride derived from seawater or brine (the Dow process), or by reduction of magnesium oxide in the Pidgeon process.

Magnesium and its alloys are valued for light weight and strength. Aluminum-magnesium alloys are common in aerospace and automotive applications. Magnesium oxide and magnesium hydroxide are used as refractory materials and fire retardants, and magnesium compounds appear in electronics, catalysts, and pyrotechnics.

The name magnesium derives from Magnesia, a region in Thessaly, Greece. The element was isolated in 1808 by Sir Humphry Davy through electrolysis of magnesium compounds. The informal abbreviation “Mag” is sometimes used in casual or abbreviated contexts, though standard chemical notation uses Mg.