Amethyst

Physical Properties

Hardness: 7 (Mohs scale); Color: Purple to violet; Luster: Vitreous/Glassy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65.

Formation & Geological History

Formed in hydrothermal veins and hollow cavities (geodes) within igneous rocks. The purple color is the result of irradiation and iron impurities. Highly prevalent in volcanic deposits.

Uses & Applications

Extensively used in jewelry (faceting and cabochons), as decorative display specimens, and in spiritual/metaphysical practices.

Geological Facts

Amethyst was considered a precious stone on par with diamonds until large deposits were found in Brazil. The name comes from the Greek 'amethystos', meaning 'not intoxicated', as it was once believed to prevent drunkenness.

Field Identification & Locations

Identify in the field by its hexagonal crystal habit (if present), conchoidal fracture, and ability to scratch glass. Commonly found in Brazil, Uruguay, Zambia, and Ontario, Canada.

Identified on: 4/23/2026

Mode: Standard