mineral

Amethyst Cluster

Silicon Dioxide (Quartz variety: Amethyst) - SiO2

Hardness: 7 on Mohs scale. Color: Purple to violet, sometimes with lighter or darker zones. Luster: Vitreous (glassy). Crystal Structure: Trigonal (hexagonal crystal system). Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Purple to violet, sometimes with lighter or darker zones
Luster: Vitreous (glassy)

Identified July 30, 2026More mineral →

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Physical properties

Formation & geological history

Formed in hydrothermal veins and cavities (vugs or geodes) within volcanic rocks, where silica-rich solutions cooled and crystallized over millions of years.

Uses & applications

Widely used in jewelry, ornamental carvings, crystal healing, and as collector specimens.

Geological facts

Amethyst gets its purple color from natural irradiation and trace amounts of iron (and other transition metal impurities) substituting for silicon in the crystal lattice.

Field identification & locations

Identified by its distinctive purple color and hexagonal crystal termination points. Commonly found in Brazil, Uruguay, Zambia, and parts of the United States.

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