mineral

Amethyst (Quartz variety)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale. Color: Pale lilac to deep purple. Luster: Vitreous/Glassy. Crystal Structure: Hexagonal (trigonal). Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Pale lilac to deep purple
Luster: Vitreous/Glassy

Identified June 21, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale. Color: Pale lilac to deep purple. Luster: Vitreous/Glassy. Crystal Structure: Hexagonal (trigonal). Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Formation & geological history

Formed in igneous or metamorphic rocks through hydrothermal processes, often found inside geodes or as veins. The purple color is caused by irradiation, impurities of iron, and the presence of trace elements.

Uses & applications

Primary use is in jewelry (faceted or cabochon), ornamental carvings, and as a popular collector specimen. Historically used as a protective amulet.

Geological facts

The name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', due to a belief that the stone protected its owner from drunkenness. It is the birthstone for February.

Field identification & locations

Identify in the field by its purple hue and ability to scratch glass but not topaz. Commonly found in Brazil, Uruguay, and various parts of the USA and Canada. Look for crystal habits in volcanic cavities.