Rock Identifier
Amethyst (Silicon Dioxide (SiO2) with iron impurities) — mineral
mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 on Mohs scale. Color: Pale lilac to deep purple, often with zones of white or clear quartz. Luster: Vitreous (glassy). Crystal Structure: Hexagonal (Trigonal). Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Hardness
7 on Mohs scale
Luster
Vitreous (glassy)
Identified More mineral

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Physical properties

Hardness: 7 on Mohs scale. Color: Pale lilac to deep purple, often with zones of white or clear quartz. Luster: Vitreous (glassy). Crystal Structure: Hexagonal (Trigonal). Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Formation & geological history

Formed in hydrothermal veins or as linings in geodes within igneous or volcanic rocks. The purple color is caused by natural irradiation, iron impurities, and the presence of trace elements. Found in rocks ranging from millions to billions of years old.

Uses & applications

Primarily used as a semi-precious gemstone in jewelry (rings, necklaces, earrings) and as decorative specimens or metaphysical crystals in collecting.

Geological facts

Amethyst was considered a 'Cardinal Gem' and was historically as valuable as diamonds until large deposits were found in Brazil. Its name comes from the Ancient Greek word 'amethystos', meaning 'not intoxicated', as it was believed to prevent drunkenness.

Field identification & locations

Identify in the field by its purple hue, lack of cleavage, and ability to scratch glass. Commonly found in Brazil, Uruguay, Zambia, and Ontario, Canada. This specific specimen appears to be a 'tumbled' stone, polished using a rock tumbler.