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Corundum: Difference between revisions
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Corundum occurs as a mineral in mica schist, gneiss, and some marbles in metamorphic terranes. It also occurs in low silica igneous syenite and nepheline syenite intrusives. Other occurrences are as masses adjacent to ultramafic intrusives, associated with lamprophyre dikes and as large crystals in pegmatites. Because of its hardness and resistance to weathering, it commonly occurs as a detrital mineral in stream and beach sands. | Corundum occurs as a mineral in mica schist, gneiss, and some marbles in metamorphic terranes. It also occurs in low silica igneous syenite and nepheline syenite intrusives. Other occurrences are as masses adjacent to ultramafic intrusives, associated with lamprophyre dikes and as large crystals in pegmatites. Because of its hardness and resistance to weathering, it commonly occurs as a detrital mineral in stream and beach sands. | ||
Every possible corundum morphology—bipyramidal, prismatic, tabular, and rhombohedral—was found in inclusions in the igneous matrix of the [[Forerunner]] artifact recovered from the [[Côte d'Azur Museum of Natural History]] on [[Sigma Octanus IV]]. When scanned from tip to base with neutron imagers, a pattern of squares, triangles, bars, and dots was produced.<ref> | Every possible corundum morphology—bipyramidal, prismatic, tabular, and rhombohedral—was found in inclusions in the igneous matrix of the [[Forerunner]] artifact recovered from the [[Côte d'Azur Museum of Natural History]] on [[Sigma Octanus IV]]. When scanned from tip to base with neutron imagers, a pattern of squares, triangles, bars, and dots was produced.<ref>''[[Halo: The Fall of Reach]]'', Chapter 24</ref> | ||
==Sources== | ==Sources== | ||
<references/> | <references/> | ||
[[Category:Chemical Compounds]] | [[Category:Chemical Compounds]] | ||