mineral

Amethyst

Quartz (Silicon Dioxide) SiO2 + Fe4

Hardness: 7 on Mohs scale; Color: light violet to deep purple; Luster: vitreous; Crystal system: Hexagonal (trigonal); Cleavage: none; Specific gravity: 2.65.

Hardness: 7 on Mohs scale
Color: light violet to deep purple
Luster: vitreous

Identified July 5, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: light violet to deep purple; Luster: vitreous; Crystal system: Hexagonal (trigonal); Cleavage: none; Specific gravity: 2.65.

Formation & geological history

Formed in hydrothermal veins or geodes within volcanic rocks when silica-rich water rich in iron impurities crystallizes over millions of years. Its purple color comes from irradiation of iron impurities.

Uses & applications

Widely used for jewelry (birthstones), ornamental carvings, meditation crystals, and geological specimens for collectors.

Geological facts

Amethyst was considered one of the five cardinal gemstones until the 18th century. The name comes from the Ancient Greek word 'amethystos', meaning 'not intoxicated', due to a belief that the stone protected its owner from drunkenness.

Field identification & locations

Identify in the field by its distinct purple hue and hexagonal crystal terminations. Commonly found in Brazil, Uruguay, and South Korea. Collectors should look for deep saturation and good clarity.