mineral

Amethyst on Agate

Crystalline Quartz (SiO2) with trace Iron (Fe3+)

AI-generated identification · may be incorrect

Hardness: 7 (Mohs scale), Color: Pale to medium purple crystals on translucent grey/blue agate. Luster: Vitreous. Crystal Structure: Trigonal. Cleavage: None/Conchoidal fracture.

Luster: Vitreous

Identified July 4, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: Pale to medium purple crystals on translucent grey/blue agate. Luster: Vitreous. Crystal Structure: Trigonal. Cleavage: None/Conchoidal fracture.

Formation & geological history

Forms inside volcanic geodes or cavities through hydrothermal processes where silicon-rich water reacts with trace iron and radiates naturally to create purple hues. Primarily Cenozoic to Mesozoic era.

Uses & applications

Extensively used in jewelry (rings, necklaces), spiritual practices, decorative lapidary arts, and mineral collecting.

Geological facts

Amethyst was once considered one of the 'Cardinal Gems' until large deposits were found in Brazil, making it more accessible. Its name comes from the Greek 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identified by its characteristic purple hexagonal crystal terminations. Found commonly in Brazil, Uruguay, and Madagascar. Collectors look for deep saturation of color and clarity in the crystal tips.