mineral

Amethyst

Silicon dioxide (SiO2) with iron impurities

Hardness: 7 on Mohs scale; Color: Pale lavender to deep royal purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Pale lavender to deep royal purple
Luster: Vitreous (glassy)

Identified July 8, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Pale lavender to deep royal purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Forms in geothermal environments, typically as druzy linings within volcanic gas cavities (vugs or geodes). The purple color is the result of irradiation of trivalent iron (Fe3+) impurities and the presence of trace elements within the quartz crystal lattice.

Uses & applications

Primarily used in jewelry, as gemstone specimens for collectors, and in decorative ornamental carvings. It is also significant in various spiritual and metaphysical practices.

Geological facts

Amethyst was considered a Cardinal Gem until the 18th century, ranked alongside diamond and ruby in value, until large deposits were found in Brazil. Its name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to protect against drunkenness.

Field identification & locations

Identified by its purple color and hexagonal prism crystal habits. Look for it in basaltic rocks or volcanic geodes. For collectors, higher value is placed on deep purple specimens with no visible zoning and high clarity.