mineral

Amethyst

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on the Mohs scale. Color ranges from pale lilac to deep purple. Luster: Vitreous (glassy). Crystal structure: Trigonal. Cleavage: None (conchoidal fracture). Specific gravity: 2.65.

Hardness: 7 on the Mohs scale
Luster: Vitreous (glassy)

Identified August 1, 2026More mineral →

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Physical properties

Hardness: 7 on the Mohs scale. Color ranges from pale lilac to deep purple. Luster: Vitreous (glassy). Crystal structure: Trigonal. Cleavage: None (conchoidal fracture). Specific gravity: 2.65.

Formation & geological history

Forms within gas cavities (vesicles) in basaltic rocks, or as linings in hydrothermal veins, where silica-rich water deposits quartz crystals over millions of years under moderate temperatures.

Uses & applications

Widely used in jewelry (rings, necklaces, earrings), as a gemstone, for decorative ornamental objects, and by collectors or spiritual practitioners.

Geological facts

Amethyst was once considered one of the cardinal gemstones of high value until large deposits were discovered in Brazil. Its purple color is caused by irradiation and trace amounts of iron impurities.

Field identification & locations

Identified by its distinctive purple color and conchoidal fracture. Commonly found in Brazil, Uruguay, Zambia, and the United States (such as Arizona and Colorado).