mineral

Amethyst

SiO2 (Silicon Dioxide with iron impurities)

Hardness: 7 on Mohs scale; Color: Purple, violet, Lavender; Luster: Vitreous/glassy; Crystal structure: Trigonal; Cleavage: None; Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Purple, violet, Lavender
Luster: Vitreous/glassy

Identified May 31, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple, violet, Lavender; Luster: Vitreous/glassy; Crystal structure: Trigonal; Cleavage: None; Specific gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and cavities (geodes) of igneous rocks when silica-rich water cools. The purple color comes from irradiation and iron impurities. Geological age ranges from millions to billions of years depending on the host deposit.

Uses & applications

Primarily used in jewelry (as a semi-precious gemstone), decorative items, spiritual/metaphysical collecting, and industrial use in glassmaking or abrasives when of lower quality.

Geological facts

Amethyst is the birthstone for February. Ancient Greeks believed it could prevent intoxication; the name comes from the Greek word 'amethystos', meaning 'not drunken'.

Field identification & locations

Identify by its distinctive purple color and lack of cleavage (it has conchoidal fracture). Often found in basalt vugs and geodes. Common locations include Brazil, Uruguay, and Madagascar.