mineral

Amethyst

Silicon Dioxide (SiO2) with Fe3+ impurities

Hardness: 7 on Mohs scale; Color: Purple/Violet; Luster: Vitreous/Glassy; Crystal structure: Hexagonal/Trigonal (six-sided prisms); Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Purple/Violet
Luster: Vitreous/Glassy

Identified April 2, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple/Violet; Luster: Vitreous/Glassy; Crystal structure: Hexagonal/Trigonal (six-sided prisms); Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and basaltic geodes. The purple color comes from irradiation of trivalent iron impurities within the quartz crystal structure. Geologic ages vary widely from billions of years to more recent Cenozoic formations.

Uses & applications

Primarily used in jewelry, as decorative display specimens, and in metaphysical or alternative healing practices. High-quality transparent stones are faceted into gemstones.

Geological facts

Amethyst is the birthstone for February. In ancient Greece, it was believed that wearing or drinking from vessels made of amethyst would prevent drunkenness; the name comes from the Greek word 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identify in the field by its distinct purple color, 7 hardness (scratches glass), and crystal habit. Common locations include Brazil, Uruguay, Zambia, and South Korea. Look for them inside hollow volcanic rocks (geodes).

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