mineral

Amethyst (Tumbled Quartz)

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7.0 on Mohs scale; Color: Pale lavender to deep purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal/Trigonal; Cleavage: None (Conchoidal fracture); Specific Gravity: 2.65

Hardness: 7
Color: Pale lavender to deep purple
Luster: Vitreous (glassy)

Identified May 25, 2026More mineral →

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Physical properties

Hardness: 7.0 on Mohs scale; Color: Pale lavender to deep purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal/Trigonal; Cleavage: None (Conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and basaltic geodes. The purple color is caused by irradiation of trivalent iron (Fe3+) impurities in the crystal lattice of quartz.

Uses & applications

Primarily used in jewelry (rings, necklaces), ornamental carvings, and widely collected as a healing crystal or decorative stone. Small tumbled stones are used in fish tanks or as vase fillers.

Geological facts

Amethyst was once considered one of the 'Cardinals' gems, as valuable as diamonds, until large deposits were found in Brazil. The name comes from the Greek 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identify by its characteristic purple hue and ability to scratch glass. Tumbled specimens feel smooth and cool to the touch. It is common in Brazil, Uruguay, Zambia, and South Korea.

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