gemstone
Star Ruby
Corundum (Al2O3)
AI-generated identification · may be incorrectHardness of 9 on the Mohs scale, purplish-red to pink color, subadamantine to vitreous luster, trigonal crystal system, and displays asterism as a six-rayed star caused by rutile needle inclusions.
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Physical properties
Hardness of 9 on the Mohs scale, purplish-red to pink color, subadamantine to vitreous luster, trigonal crystal system, and displays asterism as a six-rayed star caused by rutile needle inclusions.
Formation & geological history
Formed in metamorphic marble and igneous rocks under high temperatures and pressures over millions of years.
Uses & applications
Extensively used in high-end jewelry and collector specimens due to its rare optical phenomenon.
Geological facts
The star effect is known as asterism and moves across the stone as the angle of light changes. Synthetic star rubies are common in the market, making natural specimens highly prized.
Field identification & locations
Identified by its distinct six-pointed star under a direct light source and high scratch resistance. Commonly sourced from Myanmar, Sri Lanka, and Thailand.
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