mineral

Amethyst Quartz

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 on Mohs scale. Color: Violet to deep purple hues with clear quartz. Luster: Vitreous (glassy). Crystal Structure: Hexagonal (trigonal), often found in druzy clusters or prismatic crystals. Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Violet to deep purple hues with clear quartz
Luster: Vitreous (glassy)

Identified June 24, 2026More mineral →

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Physical properties

Formation & geological history

Formed in hydrothermal veins or cavities (geodes) within igneous rocks like basalt. The purple color comes from irradiation of iron impurities within the quartz lattice. Most specimens are from the Phanerozoic eon.

Uses & applications

Widely used in jewelry (rings, necklaces), as decorative display pieces (cathedrals/geodes), and in alternative medicine/metaphysical practices.

Geological facts

Amethyst is the official birthstone of February. The name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to prevent drunkenness.

Field identification & locations

Identify by its characteristic purple color and hexagonal prism shapes. Commonly found in Brazil, Uruguay, and Africa. Collectors should look for deep uniform color and lack of visible inclusions.

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Mineral/Rock

Banded Gneiss (River Rock/Pebble)

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Metamorphic Rock

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mineral