gemstone

Amethyst

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale. Color: Light to dark purple or violet. Luster: Vitreous (glassy). Crystal structure: Trigonal (hexagonal system), typically forming prismatic crystals with pyramidal terminations. Cleavage: None (exhibits conchoidal fracture). Specific gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Light to dark purple or violet
Luster: Vitreous (glassy)

Identified August 5, 2026More gemstone →

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Physical properties

Formation & geological history

Forms within gas cavities (vesicles) in basaltic volcanic rocks, or as hydrothermal veins, where silica-rich solutions containing trace amounts of iron precipitate slowly at low to moderate temperatures over millions of years.

Uses & applications

Widely used as a gemstone in jewelry, decorative items, and as a popular specimen for mineral collectors and crystal healing.

Geological facts

Amethyst derives its purple color from natural irradiation and trace amounts of iron impurities substituting for silicon in the crystal lattice. The coordinates provided near Las Vegas, Nevada sit near areas where various quartz varieties and pegmatite minerals can be found regionally.

Field identification & locations

Easily identified by its distinct purple coloration and hexagonal crystal form with pyramidal ends. Major global deposits are found in Brazil, Uruguay, Zambia, and parts of the United States.