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A
.gov website belongs to an official
government organization in the United States.
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A lock (
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information only on official, secure websites.
Schematic representation: (a) silicon tetrahedron, (b) magnesium and/or aluminum octahedron. In both cases, a general diagram is presented, a front view and a top view. 
oxygen, 
silicon, 
magnesium/aluminum. Adapted from https://www.edafologia.net/, last visited 12 May 2021.
