mineral

Alexandrite in Matrix

Chrysoberyl (BeAl2O4 with Chromium)

Hardness: 8.5 on Mohs scale; Color: Green in daylight, red/purplish in incandescent light; Luster: Vitreous; Crystal structure: Orthorhombic; Cleavage: Distinct in one direction; Specific gravity: 3.70 - 3.78

Hardness: 8
Color: Green in daylight, red/purplish in incandescent light
Luster: Vitreous

Identified March 4, 2026More mineral →

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Physical properties

Formation & geological history

Formed in granitic pegmatites and mica schists where beryllium and chromium contact one another under high pressure and temperature. Primary deposits occur in metamorphic environments.

Uses & applications

Extremely valuable gemstone used in high-end jewelry; smaller or included specimens are popular among mineral collectors.

Geological facts

First discovered in Russia's Ural Mountains in 1830 and named after Tsar Alexander II. It is famous for its dramatic 'emerald by day, ruby by night' color change caused by the absorption of light in a narrow yellow spectrum.

Field identification & locations

Identified in the field by its high hardness (scratches quartz) and the signature color shift under different light sources. Commonly found in the Ural Mountains (Russia), Brazil, Sri Lanka, and Tanzania.

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