“According to one contention, magnesium will eventually replace iron as the world’s basic constructional raw material. Hence, it might be feasible to call the next age of man the ‘magnesium age.’ The element appears to be the only ‘basic’ material of which the supply is inexhaustible: one cubic mile of sea water contains 9.2 billion pounds of metal in the form of magnesium chloride. It is the lightest of the structural metals, and magnesium’s so-called ‘fire hazard’ is only a factor when handling fine powders or the molten metal. However, if magnesium is to become the prime raw material it is not likely to do so for centuries. Its competitors—iron and steel, aluminum and structural plastics—would have to reach a state of depleted supply and high prices.”

Scientific American, August 1946

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