mineral

Amethyst

Amethyst (Silicon Dioxide, SiO2)

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

Hardness: 7 on Mohs scale
Color: light lilac to deep purple
Luster: Vitreous

Identified May 9, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in hydrothermal veins or geodes within volcanic rocks where silica-rich water deposits crystals over time. Often found in basalt vugs. Geologic age varies by location, often associated with Mesozoic to Cenozoic formations.

Uses & applications

Extensively used in jewelry, as decorative collector specimens (geodes and clusters), and in metaphysical practices. Historically used to carve drinking vessels and seals.

Geological facts

The name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to protect its owner from drunkenness. It was once considered a Cardinal Gem along with diamond, sapphire, ruby, and emerald.

Field identification & locations

Identify by its distinct purple hue and quartz-like transparency. In the field, look for hexagonal prisms with pyramidal endings. Major sources include Brazil, Uruguay, and Zambia.