mineral

Amethyst (Tumbled)

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 on Mohs scale; Color: Purple, violet, or lavender; Luster: Vitreous (glassy); Crystal structure: Trigonal; Cleavage: None; Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Purple, violet, or lavender
Luster: Vitreous (glassy)

Identified May 19, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple, violet, or lavender; Luster: Vitreous (glassy); Crystal structure: Trigonal; Cleavage: None; Specific gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or geodes when silica-rich water fills cavities in volcanic rocks. The purple color is caused by irradiation of iron impurities within the quartz structure.

Uses & applications

Primarily used for jewelry (cabochons, beads, faceted stones), ornamental carvings, and widely collected as metaphysical or decorative specimens.

Geological facts

Until the discovery of large deposits in Brazil in the 19th century, amethyst was considered one of the 'Cardinal Gems' and was as expensive as diamonds and rubies.

Field identification & locations

Identify by its distinctive purple color and hexagonal crystal habit in raw form. Commonly found in Brazil, Uruguay, Zambia, and South Korea. Collectors should look for deep, uniform color and transparency.

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