gemstone

Amethyst

Quartz (Silicon Dioxide, SiO2)

Hardness of 7 on the Mohs scale, deep purple color due to iron irradiation and trace elements, vitreous (glassy) luster, hexagonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.

Identified August 3, 2026More gemstone →

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Physical properties

Formation & geological history

Forms in gas cavities (vesicles) of volcanic rocks, hydrothermal veins, and metamorphic rocks through the crystallization of silica-rich solutions containing iron impurities over millions of years.

Uses & applications

Widely used in fine jewelry, rings, necklaces, decorative carvings, and as a popular collector's mineral specimen or in crystal healing practices.

Geological facts

Amethyst was once considered one of the cardinal gemstones of high value alongside diamond, ruby, sapphire, and emerald until large deposits were discovered in Brazil. Its name comes from the ancient Greek word amethystos, meaning 'not drunken', as the ancient Greeks believed it protected the wearer from intoxication.

Field identification & locations

Easily identified by its distinct purple coloration and hardness (scratches glass easily). Commonly sourced from Brazil, Uruguay, Zambia, and parts of the United States.