Amethyst
Silicon Dioxide (SiO2) with iron impurities
Rock Type: mineral

Physical Properties
Hardness: 7 (Mohs scale); Color: Purple, violet, or pale lavender; Luster: Vitreous/glassy; Crystal structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65
Formation & Geological History
Formed in cavities (geodes) of igneous rocks, specifically basalt, or in hydrothermal veins. The purple color comes from irradiation of iron impurities within the quartz crystal lattice.
Uses & Applications
Primarily used as a gemstone in jewelry (rings, necklaces, earrings), as ornamental carvings, and it is a very popular specimen for mineral collectors.
Geological Facts
Amethyst was once considered as valuable as diamonds or rubies until large deposits were found in Brazil. The name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to prevent drunkenness.
Field Identification & Locations
Identify by its distinct purple hue and 6-sided crystal habit when unpolished. It can be found globally with major deposits in Brazil, Uruguay, and Zambia. In the field, it is often found inside vugs or large rocky bubbles.
Identified on: 4/23/2026
Mode: Standard