mineral
Amethyst on Agate
Crystalline Quartz (SiO2) with trace Iron (Fe3+)
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
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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.
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