mineral

Amethyst (as seen in jewelry)

Amethyst (Silicon Dioxide SiO2 + Fe4+)

Hardness: 7 Mohs scale; Color: Purple to violet; Luster: Vitreous; Crystal Structure: Hexagonal (trigonal); Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Hardness: 7 Mohs scale
Color: Purple to violet
Luster: Vitreous

Identified March 3, 2026More mineral →

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Physical properties

Hardness: 7 Mohs scale; Color: Purple to violet; Luster: Vitreous; Crystal Structure: Hexagonal (trigonal); Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and cavities (geodes) of igneous rocks. Its purple color comes from irradiation of trivalent iron (Fe3+) in the quartz structure. Geological age varies by deposit, ranging from millions to billions of years old.

Uses & applications

Primary use is in jewelry (rings, necklaces) and as a semi-precious gemstone for collectors. It is also highly popular in decorative arts and metaphysical practices.

Geological facts

Amethyst was considered one of the Cardinal gems until the 18th century. The name comes from the Greek 'amethystos', meaning 'not intoxicated', as it was anciently believed to prevent drunkenness.

Field identification & locations

In the field, it is identified by its purple hue and hexagonal crystal habit. It is commonly found in Brazil, Uruguay, Zambia, and South Korea. For this specific ring, look for symmetry in the cut and saturation of color.

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