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What element are you as likely to find in the ocean as in an airplane or your own body? Magnesium, of course! This alkaline-earth metal belongs to group 2 on the periodic table, and has a hand in everything from the function of cellular life to the fireworks displays you watch on the 4th of July. 

Paradoxically Absent

Despite being the eighth most abundant element in the Earth’s crust, Magnesium only occurs in nature in compounds. Its isolated state is as a silvery-white metal that’s always ready to ignite and burn brightly (even when submerged in water after ignition), but the versions of Magnesium with which you’re familiar are probably a bit tamer. 

In another layer of strangeness, Magnesium is the third most abundant structural metal (and the lightest) behind aluminum and iron, a shocking fact considering that the metallic form does not happen on its own. 

Despite its noticeable absence in the isolated form, Magnesium still exists in great natural abundance in compounds. In fact, Magnesium is the basis of chlorophyll, which allows plants to perform photosynthesis. It is also critical to the function of hundreds of enzymes in the human body, and so every person stores about 20 grams of Magnesium in their bodies at all times, primarily in their bones. 

Another Davy Discovery

Magnesium was isolated for the first time in 1808 by an accomplished scientist named Sir Humphrey Davy (he also discovered sodium and potassium). He completed the isolation by evaporating mercury from a magnesium amalgam (an alloy). 

Magnesium was chosen as the name due to its presence in the mineral Magnesia, which was named for the region in Greece where it was first discovered. Now, commercial Magnesium is obtained as a byproduct of electrolysis of Magnesium Chloride. 

Since it doesn’t occur in isolation on its own, it should come as no surprise that Magnesium compounds are abundant. It combines with carbon to create magnesite and dolomite (where it is primarily found); with chloride as carnallite; with sulfur to create kieserite; and with many other elements in varying degrees. Magnesium can also be found as a quite plentiful component of seawater; in fact, this element is what gives the water its characteristic bitter taste. 

Epsom salt, airplanes, and fireworks

Since it is a critical component of life on Earth, Magnesium has a number of functions within the healthcare industry. Milk of magnesia, epsom salts, and a number of other compounds serve to improve daily life in an assortment of ways. 

Magnesium alloys are commonly used to manufacture mobile devices like laptops, or items like luggage that must be sturdy but able to move easily. 

Being that it is the lightest structural metal, Magnesium is an obvious choice to build metal objects that need to carry as little weight as possible, like airplanes and cars. However, because of the fact that Magnesium is so willing to ignite, it is not a viable option on its own. That’s why Magnesium-Aluminum alloy is a safer alternative that still utilizes the strong suits of Magnesium (namely that it is one third less dense than aluminum), but downplays the dangers. 

This material’s tendency to spark up and blaze isn’t all bad, though. Thanks to its reactivity, Magnesium is helpful in creating flares and fireworks since it not only burns, but it also burn incredibly brightly. 

Magnesium may not be visible in its metallic form, but it’s all around you and even in you, ensuring that the world (and your body) run just the way that they’re meant to.