mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 (Mohs scale), Color: Purple to deep violet, Luster: Vitreous, Crystal structure: Trigonal (hexagonal prisms), Cleavage: None (conchoidal fracture), Specific gravity: 2.65

Identified April 29, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: Purple to deep violet, Luster: Vitreous, Crystal structure: Trigonal (hexagonal prisms), Cleavage: None (conchoidal fracture), Specific gravity: 2.65

Formation & geological history

Found within geodes in igneous rocks or as veins in hydrothermal deposits. Formed during the cooling of molten rock when gas bubbles trap mineral-rich water, crystallizing over millions of years. Color results from irradiation of iron impurities.

Uses & applications

Primarily used in jewelry (faceting into gemstones), ornamental sculptures, and as a popular mineral specimen for collectors and home decor.

Geological facts

The name comes from the Greek word 'amethystos', meaning 'not intoxicated', as it was believed to prevent drunkenness. It is the birthstone for February. Large geodes are commonly found in Brazil and Uruguay.

Field identification & locations

Identified by its distinctive purple color and hexagonal prism shape. Often found in basalt cavities. Collectors should look for deep uniform saturation and high clarity in natural specimens.

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Mineral/Rock

Banded Gneiss (River Rock/Pebble)

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Metamorphic Rock

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