mineral

Alexandrite

Chrysoberyl (BeAl2O4 with Chromium impurities)

AI-generated identification · may be incorrect

Hardness: 8.5 (Mohs scale); Color: Green to bluish-green in daylight, purplish-red in incandescent light; Luster: Vitreous; Crystal structure: Orthorhombic; Cleavage: One direction (distinct); SG: 3.70-3.78

Hardness: 8
Luster: Vitreous

Identified April 11, 2026More mineral →

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Physical properties

Formation & geological history

Formed in pegmatites and metamorphic environments where beryllium and chromium meet, which is geologically rare. Significant deposits date back to the 19th-century Ural Mountains.

Uses & applications

Primarily used as a high-value gemstone in fine jewelry and as a prized specimen for mineral collectors.

Geological facts

Known as 'Emerald by day, Ruby by night' due to its extreme pleochroism. It was named after Tsar Alexander II of Russia because it was discovered on his birthday.

Field identification & locations

Identify by verifying the color change effect (Alexandrite effect) under different light sources. Commonly found in Russia, Brazil, Sri Lanka, and East Africa.