gemstone

Amethyst (Large Cluster)

Silicon Dioxide (SiO2) with iron impurities

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

Hardness: 7 Mohs
Color: Pale to deep violet
Luster: Vitreous (glassy)

Identified July 20, 2026More gemstone →

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Physical properties

Hardness: 7 Mohs; Color: Pale to deep violet; 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. This specimen likely originates from volcanic cavities where silica-rich fluids crystallized over millions of years.

Uses & applications

Highly valued for ornamental use, metaphysical practices, gemstone jewelry, and as a decorative interior specimen.

Geological facts

The purple color comes from irradiation, iron impurities, and the presence of trace elements. It was once considered as valuable as diamonds until large deposits were found in Brazil.

Field identification & locations

Identify by its purple hue and hexagonal crystal points. Large clusters like this are often sourced from Uruguay or Brazil. Look for natural crystal faces rather than glass imitations which lack internal inclusions.

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