mineral

Amethyst (as a jewelry accent)

Amethyst (Silicon Dioxide SiO2 with Iron impurities)

Hardness: 7 on Mohs scale; Color: Purple, violet, to deep lavender; Luster: Vitreous (glass-like); Crystal structure: Trigonal (Hexagonal); Cleavage: None/Conchoidal fracture; Specific gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Purple, violet, to deep lavender
Luster: Vitreous (glass-like)

Identified March 15, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple, violet, to deep lavender; Luster: Vitreous (glass-like); Crystal structure: Trigonal (Hexagonal); Cleavage: None/Conchoidal fracture; Specific gravity: 2.65.

Formation & geological history

Formed in hydrothermal veins and basaltic geodes. Secondary mineralization occurs when silica-rich water flows through rock cavities, often over millions of years.

Uses & applications

Primarily used as a gemstone in jewelry (rings, brooches, necklaces) and for specimen collecting. High-grade pieces are faceted, while others are carved or tumbled.

Geological facts

Formerly considered one of the 'Cardinals' or most precious gems alongside ruby and diamond until large deposits were found in Brazil. It is the birthstone for February.

Field identification & locations

Identify by its distinct purple hue and crystal clarity. Often found in South America (Brazil, Uruguay) and Africa. In jewelry, look for high clarity and deep saturation in the purple color.

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