mineral

Amethyst

Quartz (Silicon Dioxide) - SiO2

Hardness: 7 on Mohs scale; Color: Purple, violet, or lavender; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65

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

Identified May 10, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple, violet, or lavender; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or geodes within volcanic rocks where silica-rich fluids crystallize. The purple color is caused by irradiation of iron impurities within the quartz lattice.

Uses & applications

Widely used for jewelry (faceted stones and cabochons), decorative items, spiritual/metaphysical collecting, and as a birthstone (February).

Geological facts

Amethyst was highly valued in antiquity and was once one of the five cardinal gemstones alongside diamonds, rubies, sapphires, and emeralds before large deposits were found in Brazil.

Field identification & locations

Identified by its purple hue and hexagonal crystal form. Commonly found in Brazil, Uruguay, Zambia, and South Korea. Look for the conchoidal (shell-like) fracture patterns and the ability to scratch glass.