mineral
Amethyst
Quartz (Silicon Dioxide, SiO2)
AI-generated identification · may be incorrectHardness: 7 on Mohs scale; Color: Purple, violet, dark orchid; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal system); Cleavage: None, exhibits conchoidal fracture; Specific Gravity: 2.65
- Hardness
- 7 on Mohs scale
- Color
- Purple, violet, dark orchid
- Luster
- Vitreous (glassy)
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Physical properties
Hardness: 7 on Mohs scale; Color: Purple, violet, dark orchid; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal system); Cleavage: None, exhibits conchoidal fracture; Specific Gravity: 2.65
Formation & geological history
Forms in hydrothermal veins and cavity fillings in volcanic rocks (such as basalt gas cavities or geodes), where silica-rich solutions cool and crystallize at low to moderate temperatures.
Uses & applications
Widely used in jewelry, lapidary arts, decorative items, and prized by crystal collectors.
Geological facts
Amethyst was once considered one of the cardinal gemstones of high value until large deposits were discovered in Brazil. Its purple color is caused by irradiation and trace amounts of iron.
Field identification & locations
Easily identified by its distinct purple color and hexagonal crystal prism shape. Commonly sourced from Brazil, Uruguay, Zambia, and the USA.
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