mineral

Amethyst

Amethyst (Silicon Dioxide, SiO2)

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

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

Identified July 8, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in hydrothermal veins and basaltic geodes. It gets its color from irradiation, iron impurities, and the presence of trace elements. Age varies by deposit, ranging from millions to hundreds of millions of years.

Uses & applications

Predominantly used as a gemstone in jewelry, as well as for decorative items, metaphysical healing collections, and industrial uses for silica.

Geological facts

Amethyst was once considered as valuable as diamonds and rubies until large deposits were discovered in Brazil in the 18th century. It is the birthstone for February.

Field identification & locations

Identify in the field by its purple hue and hexagonal crystal shape. It is commonly found in Brazil, Uruguay, Zambia, and South Korea. Collectors should look for deep, uniform color and high clarity.