mineral

Amethyst

Quartz (SiO2)

Hardness: 7 on the Mohs scale. Color: Ranges from pale lilac to deep purple. Luster: Vitreous (glassy). Crystal structure: Trigonal system, commonly forming prismatic crystals terminating in pyramids. Cleavage: None (conchoidal fracture). Specific gravity: 2.65.

Hardness: 7 on the Mohs scale
Color: Ranges from pale lilac to deep purple
Luster: Vitreous (glassy)

Identified August 3, 2026More mineral →

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Physical properties

Formation & geological history

Forms within gas cavities (vesicles) in basaltic volcanic rocks, or within sedimentary rocks, where silica-rich hydrothermal solutions deposit quartz crystals over thousands to millions of years. Irradiation and trace amounts of iron impurities produce the characteristic purple color.

Uses & applications

Widely used in jewelry as a precious gemstone, in ornamental carvings, metaphysical healing, and mineral collecting.

Geological facts

Amethyst was once considered one of the cardinal gemstones of high value until large deposits were discovered in Brazil during the 19th century. Its name comes from the ancient Greek word amethystos, meaning 'not drunken,' as the Greeks believed it protected the wearer from intoxication.

Field identification & locations

Easily identified by its distinct purple coloration and hexagonal crystal habit or quartz-like druzy clusters. Commonly found in Brazil, Uruguay, Zambia, and the United States (such as Arizona and Arkansas).