mineral

Amethyst

Amethyst (Varietal of Quartz), SiO2 with traces of Iron (Fe3+)

Hardness: 7 on Mohs scale; Color: Pale lilac to deep royal purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Pale lilac to deep royal purple
Luster: Vitreous (glassy)

Identified March 17, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Pale lilac to deep royal purple; 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 results from gamma irradiation of trace iron impurities. Most commercial specimens are from the Cretaceous period (approx. 140 million years ago).

Uses & applications

Extensively used in jewelry (faceting, cabochons), ornamental carvings, and as a popular decorative mineral specimen for collectors and metaphysical markets.

Geological facts

Until the 18th century, amethyst was considered one of the 'Cardinal Gems' alongside diamond and ruby, until large deposits in Brazil lowered its value. Ancient Greeks believed it prevented intoxication.

Field identification & locations

Identify by its purple hue, hexagonal crystal points, and lack of cleavage. Commonly found in Brazil, Uruguay, and Zambia. Collectors look for deep saturation of color and clarity within the crystal points.

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