gemstone
Ruby
Corundum (Al2O3:Cr)
AI-generated identification · may be incorrectHardness of 9 on the Mohs scale, vivid red color due to chromium, subadamantine to vitreous luster, and trigonal crystal system.
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Physical properties
Hardness of 9 on the Mohs scale, vivid red color due to chromium, subadamantine to vitreous luster, and trigonal crystal system.
Formation & geological history
Forms in metamorphic and igneous rocks, specifically marbles and aluminum-rich pegmatites, over millions of years under high pressure and temperature.
Uses & applications
Highly prized in fine jewelry and used historically in precision laser technology and mechanical watch bearings.
Geological facts
Ruby is one of the traditional cardinal gemstones and fine-quality Burmese rubies can command higher per-carat prices than diamonds.
Field identification & locations
Identified by its extreme hardness, dichroism, and distinct red fluorescence under ultraviolet light; major sources include Myanmar, Mozambique, and Madagascar.
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