mineral

Amethyst (Raw Quartz)

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 (Mohs scale); Color: Pale lavender/violet to deep purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Pale lavender/violet to deep purple
Luster: Vitreous (glassy)

Identified April 12, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Pale lavender/violet to deep purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or geodes when silica-rich water cools. The purple color is caused by irradiation of trivalent iron (Fe3+) impurities. They can form in volcanic cavities or sedimentary rocks.

Uses & applications

Primarily used in jewelry as a gemstone, decorative ornaments, and highly valued by metaphysical and mineral collectors.

Geological facts

Amethyst was once valued as highly as diamonds until large deposits were found in Brazil in the 1700s. Its name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', due to a belief it protected against drunkenness.

Field identification & locations

Identify in the field by its distinct purple hue and harder-than-glass surface (glass is ~5.5). Commonly found in Brazil, Uruguay, Africa, and parts of the USA like Arizona. It will not have a cleavage plane and breaks like glass.

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