Amethyst Cluster

Amethyst (Silicon Dioxide), chemical formula: SiO2

Rock Type: mineral

Amethyst Cluster

Physical Properties

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

Formation & Geological History

Formed in hydrothermal veins or as linings in geodes. The purple color comes from irradiation of iron impurities within quartz crystals. Most major commercial deposits are found in basaltic rocks from the Cretaceous period.

Uses & Applications

Primarily used in jewelry (faceting), household decoration, and by mineral collectors for its aesthetic appeal.

Geological Facts

Amethyst is the birthstone for February. The name comes from the Greek 'amethystos', meaning 'not intoxicated', as ancient Greeks believed the stone could prevent drunkenness.

Field Identification & Locations

Identify in the field by its distinct purple hue and six-sided prismatic crystals terminating in pyramids. Commonly found in Brazil, Uruguay, and Zambia. Collectors should look for deep, uniform color and undamaged crystal tips.

Identified on: 4/16/2026

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