mineral

Amethyst

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: Purple, violet, dark orchid; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal system); Cleavage: None, exhibits conchoidal fracture; Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Purple, violet, dark orchid
Luster: Vitreous (glassy)

Identified August 7, 2026More mineral →

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Physical properties

Formation & geological history

Forms in hydrothermal veins and cavity fillings in volcanic rocks (such as basalt gas cavities or geodes), where silica-rich solutions cool and crystallize at low to moderate temperatures.

Uses & applications

Widely used in jewelry, lapidary arts, decorative items, and prized by crystal collectors.

Geological facts

Amethyst was once considered one of the cardinal gemstones of high value until large deposits were discovered in Brazil. Its purple color is caused by irradiation and trace amounts of iron.