mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 (Mohs scale); Color: Pale lilac to deep reddish-purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal/Trigonal (often found as hexagonal prisms ending in pyramids); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

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

Identified January 27, 2026More mineral →

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Physical properties

Formation & geological history

Amethyst forms in geodes or cavities within igneous rocks (primarily basalt) and hydrothermal veins. Its color results from gamma irradiation and the presence of trace iron (Fe3+) in the quartz crystal lattice. It can be found in formations ranging from millions to over a billion years old.

Uses & applications

Primarily used as a gemstone in jewelry (rings, necklaces, earrings) and as decorative carvings. It is also highly prized by mineral collectors and used in holistic metaphysical practices.

Geological facts

Amethyst was considered a Cardinal Gem (one of the five noble gems) until large deposits were found in Brazil in the 18th century. Its name comes from the Ancient Greek 'amethystos,' meaning 'not drunk,' as it was believed to protect its owner from intoxication.

Field identification & locations

Identify by its distinctive purple color and hexagonal crystal habit. It is commonly found in Brazil, Uruguay, Zambia, and South Korea. In the field, look for rocky geodes containing purple crystal linings or translucent purple fragments in riverbeds near volcanic regions.

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