mineral

Amethyst

Silicon Dioxide with Iron impurities (SiO2)

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

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

Identified March 18, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in hydrothermal veins and cavities (geodes) within igneous rocks. The purple color is caused by natural irradiation of iron impurities within the quartz crystal lattice.

Uses & applications

Primary use is in jewelry (faceted gemstones, beads, cabochons) and as decorative mineral specimens for collectors and home decor.

Geological facts

Amethyst was considered a Cardinal Gem until large deposits were found in Brazil in the 1700s. Its name comes from the Greek 'amethystos', meaning 'not intoxicated', as ancients believed it protected against drunkenness.

Field identification & locations

Identify by its characteristic purple color and hexagonal crystal habit. It is frequently found in volcanic regions like Brazil, Uruguay, and Madagascar. For collectors, look for deep 'Siberian' purple hues with red or blue flashes.

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