Definition of magnesium
: a silver-white malleable ductile light metallic element that occurs abundantly in nature and is used in metallurgical and chemical processes, in photography, signaling, and pyrotechnics because of the intense white light it produces on burning, and in construction especially in the form of light alloys — see Chemical Elements Table
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Time Traveler for magnesium
The first known use of magnesium was in 1812
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