mineral

Amethyst

Quartz (Silicon Dioxide with iron impurities), SiO2

Hardness: 7 on Mohs scale; Color: light to deep purple; Luster: vitreous (glassy); Crystal structure: trigonal/hexagonal; Cleavage: none (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: light to deep purple
Luster: vitreous (glassy)

Identified June 7, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: light to deep purple; Luster: vitreous (glassy); Crystal structure: trigonal/hexagonal; Cleavage: none (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or as linings in geodes. The purple color comes from irradiation of iron impurities within the silicon dioxide crystal structure. It can be found in rocks ranging from Pre-Cambrian to recent volcanic deposits.

Uses & applications

Widely used in jewelry (faceting, cabochons), ornamental decoration, and highly sought after by crystal collectors and metaphysical practitioners.

Geological facts

Amethyst was considered a precious stone in ancient times, on par with diamonds and rubies, until large deposits were found in Brazil in the 19th century. The name comes from the Greek 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identify in the field by its purple hue and inability to be scratched by a steel knife (hardness). Commonly found in Brazil, Uruguay, Zambia, and South Korea. Look for hexagonal crystal terminations in cavity-rich igneous rocks.

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