mineral

Amethyst

Quartz (Silicon Dioxide, SiO2) with iron impurities

Hardness: 7 on Mohs scale; Color: light to deep purple; Luster: vitreous; Crystal structure: hexagonal (trigonal); Cleavage: none (conchoidal fracture); Specific gravity: 2.65

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

Identified May 9, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: light to deep purple; Luster: vitreous; Crystal structure: hexagonal (trigonal); Cleavage: none (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Typically forms as crystals lining geodes or veins. Created when silica-rich hydrothermal fluids precipitate in cavities within igneous or metamorphic rocks during long cooling periods. Factors like gamma irradiation and iron trace elements create the purple hue.

Uses & applications

Extensively used in jewelry (faceting and cabochons), carving, and as decorative display specimens or polished towers for the metaphysical market.

Geological facts

Amethyst was considered one of the five cardinal gemstones until large deposits were found in Brazil. The name comes from the Ancient Greek word 'amethystos', meaning 'not intoxicated', as it was believed to protect the wearer from drunkenness.

Field identification & locations

Identify by its distinct purple color and 6-sided crystal habit. In the field, look for quartz veins or volcanic geodes. Collectors should watch for natural color variations and avoid glass imitations that may contain air bubbles. These specific items are carved 'towers' or 'obelisks'.

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