mineral

Amethyst

Silicon dioxide (SiO2)

Hardness: 7 on the Mohs scale; Color: purple, violet; Luster: vitreous (glassy); Crystal structure: trigonal; Cleavage: none (conchoidal fracture); Specific gravity: 2.65.

Hardness: 7 on the Mohs scale
Color: purple, violet
Luster: vitreous (glassy)

Identified July 11, 2026More mineral →

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Physical properties

Hardness: 7 on the Mohs scale; Color: purple, violet; Luster: vitreous (glassy); Crystal structure: trigonal; Cleavage: none (conchoidal fracture); Specific gravity: 2.65.

Formation & geological history

Forms in igneous rocks, primarily within geodes or cavities of volcanic rock. The purple color is caused by iron impurities and natural irradiation during crystallization.

Uses & applications

Widely used as a gemstone in jewelry (rings, necklaces, earrings), as decorative specimens for home decor, and in crystal healing practices.

Geological facts

Amethyst was once considered one of the 'Cardinal gems' and was as valuable as diamonds until large deposits were found in Brazil in the 19th century.

Field identification & locations

Identify by its distinctive purple hue and hexagonal crystal termination. Common locations include Brazil, Uruguay, South Korea, Russia, and Zambia. Collectors look for deep, uniform color and clarity.