mineral

Amethyst Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: White, clear, and purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None/Conchoidal fracture.

Hardness: 7 (Mohs scale)
Color: White, clear, and purple
Luster: Vitreous (glassy)

Identified April 6, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: White, clear, and purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None/Conchoidal fracture.

Formation & geological history

Formed in hydrothermal veins or as geodes within volcanic rocks when silica-rich fluids cool and crystallize. The purple color comes from irradiation and iron impurities in the crystal lattice.

Uses & applications

Used primarily in jewelry (gemstones), as ornamental decor (geodes/clusters), and highly popular in metaphysical/collector markets.

Geological facts

Amethyst was considered a 'Cardinal Gem' and was historically as valuable as diamonds until large deposits were discovered in Brazil in the 1700s. Its name comes from the Greek 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identified by its purple hue, hexagonal points (if crystalline), and inability to be scratched by steel. Found worldwide, with major deposits in Brazil, Uruguay, and Zambia.