mineral

Amethyst (Scepter Quartz)

Silicon Dioxide (SiO2) with Iron impurities

Hardness: 7 on Mohs scale. Color: Violet to deep purple with white quartz base. Luster: Vitreous (glassy). Crystal Structure: Trigonal/Hexagonal prism with pyramid termination. Cleavage: None (conchoidal fracture). Specific Gravity: ~2.65.

Hardness: 7 on Mohs scale
Color: Violet to deep purple with white quartz base
Luster: Vitreous (glassy)

Identified July 22, 2026More mineral →

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Physical properties

Formation & geological history

Formed in hydrothermal veins and cavities (geodes) when silica-rich fluid crystallization is subjected to natural irradiation and trace iron inclusions. Scepter quartz forms in multi-phase growth where a second generation crystal grows over an older crystal stem.

Uses & applications

Used widely as a gemstone in jewelry, decorative crystal carvings, mineral collecting specimens, and for ornamental purposes.

Geological facts

Amethyst was considered one of the cardinal gems until large deposits were discovered in Brazil in the 19th century. Ancient Greeks believed it protected against drunkenness.

Field identification & locations

Identified by its distinctive purple coloration and hexagonal crystal form. Commonly found in Brazil, Uruguay, Madagascar, Zambia, and parts of the United States like Arizona and North Carolina.

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