mineral

Amethyst

Amethyst (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: Purple, violet, or lavender; Luster: Vitreous/glassy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Purple, violet, or lavender
Luster: Vitreous/glassy

Identified May 6, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple, violet, or lavender; Luster: Vitreous/glassy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Formed in silica-rich hydrothermal veins or within geodes of volcanic rocks. The purple color is caused by trace amounts of iron and irradiation within the silica structure. Most specimens date from various volcanic episodes throughout Earth's history, often millions of years old.

Uses & applications

Widely used for jewelry (gemstones), ornamental carvings, crystal healing practices, and as a popular mineral specimen for collectors.

Geological facts

Amethyst was considered a Cardinal Gem until the 18th century, ranked alongside diamond and ruby, until large deposits were found in Brazil. Its name comes from the Greek 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identified by its distinctive purple color and hexagonal crystal habit. Common in basaltic geodes in Brazil and Uruguay. Collectors should look for vibrant, deep saturation and clarity.