gemstone
Blue Sapphire
Corundum (Al2O3)
AI-generated identification · may be incorrectHardness of 9 on the Mohs scale, vibrant blue color, adamantine to vitreous luster, and trigonal crystal system with no cleavage.
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Physical properties
Hardness of 9 on the Mohs scale, vibrant blue color, adamantine to vitreous luster, and trigonal crystal system with no cleavage.
Formation & geological history
Forms within aluminum-rich metamorphic or igneous rocks like pegmatites and basalts under high pressure and temperature over millions of years.
Uses & applications
Widely used in high-end fine jewelry, luxury watches, and industrial applications such as scratch-resistant windows.
Geological facts
A natural 8.5-carat untreated blue sapphire of high clarity is extremely rare and valuable, though synthetic flame-fusion or lab-grown variants are common.
Field identification & locations
To test authenticity, check for natural inclusions under magnification or verify hardness; a true sapphire easily scratches glass. Note: 8.5 carats equals 1700 mg, matching your note, but authenticity requires physical testing.
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