 From the ground
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| Although magnesium is found in over 60 minerals, but only dolomite (CaMg(CO3)2), magnesite (MgCO3), brucite (Mg(OH)2), carnallite (KMgCl3.6(H2O)), talc (Mg3Si4O10(OH)2), and olivine ((Mg,Fe)2SiO4) are of commercial importance.
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| In the United States this metal is principally obtained by electrolysis of fused magnesium chloride from brines, wells, and sea water:
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cathode: Mg2+ + 2e-  Mg
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| anode: 2Cl- Cl2(gas) + 2e- |
| The United States has traditionally been the major world supplier of this metal, supplying 45% of world production even as recently as 1995.
Today, the US market share is at 7%, with a single domestic producer left, US Magnesium, a company born from now-defunct Magcorp.
As of 2005 China has taken over as the dominant supplier, pegged at 60% world market share, which increased from 4% in 1995. Unlike the above
described electrolytic process, China is almost completely reliant on a different method of obtaining the metal from its ores, the silicothermic Pidgeon process
(the reduction of the oxide at high temperatures with silicon).
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