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Learn All About Magnesia


A collection of minerals from magnesium-rich sources.

What is Magnesia?

Magnesia is a term used to describe various essential minerals from magnesium-rich sources. Magnesium makes up two percent of the earth’s crust and is the eighth most plentiful element. It is the third most abundant element found in sea water. The two most important magnesium minerals are magnesite and brucite. Magnesite is the most common source of magnesia and serves many important commercial applications. Magnesia is produced from magnesite ore or is extracted from seawater and brines as magnesium hydroxide. 

The two most commercially important magnesia products are dead-burned magnesia and caustic-calcined magnesia. 

  • Magnesium was first discovered outside the Greek city of Magnesia.
  • A Nobel Prize was awarded to Richard Willstatter in 1915 for describing magnesium as an essential element in the structure of chlorophyll in plants.

Where to Find Magnesia

Uses for Magnesia

Steel & Refractory Materials Dead-burned magnesia, also known as refractory magnesia, is the primary component in refractory materials. Refractory materials are nonmetallic substances that are extremely heat resistant. They are used as the linings in furnaces, kilns, and reactors. The steel industry is the largest user of refractory magnesia.
Agriculture Caustic-calcined magnesia promotes plant and livestock health. In fact, it is an essential mineral for both. In plants, magnesium is vital for photosynthesis. In animals, magnesium prevents an often-fatal disorder known as hypomagnesia, or grass tetany. 
Environmental Protection Caustic-calcined magnesia is used to treat industrial wastewater by removing silica and precipitating heavy metals. It is used to reduce air pollution by stripping sulfur dioxide from industrial air emissions. Its absorbent properties are used to clean up hazardous chemical spills, and it is used to render metal-bearing wastes nonhazardous.
Construction & Industrial Application In construction, caustic-calcined magnesia is used to make magnesium oxychloride and oxysulfate cements that are widely used in the flooring industry. Other industrial applications include use by the oil drilling industry in drilling muds, and by the rubber industry as a vulcanizing agent.
Healthcare & Wellness Magnesia is used in comforting consumer products such as milk of magnesia and Epsom salts.

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