mineral

Alexandrite in Matrix

Chrysoberyl (BeAl2O4 with Chromium impurities)

Hardness: 8.5 (Mohs scale), Color: Pleochroic (green in daylight, reddish-purple in incandescent light), Luster: Vitreous, Crystal Structure: Orthorhombic, Specific Gravity: 3.5-3.8

Hardness: 8

Identified March 2, 2026More mineral →

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Physical properties

Hardness: 8.5 (Mohs scale), Color: Pleochroic (green in daylight, reddish-purple in incandescent light), Luster: Vitreous, Crystal Structure: Orthorhombic, Specific Gravity: 3.5-3.8

Formation & geological history

Formed in granitic pegmatites and mica schists through the rare geochemical interaction of beryllium and chromium, typically in Precambrian geological environments.

Uses & applications

A highly prized gemstone for fine jewelry and a prestigious specimen for mineral collectors due to its rarity and dramatic color-change property.

Geological facts

First discovered in the Ural Mountains of Russia in 1830 and named after Tsar Alexander II; it is known as 'Emerald by day, Ruby by night'.

Field identification & locations

Identify by its extreme hardness and dramatic color shift under different light sources. Commonly found in Russia, Brazil, Tanzania, and Sri Lanka.

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