mineral

Amethyst cluster

Quartz, SiO₂ (purple variety: amethyst)

AI-generated identification · may be incorrect

Hardness 7 Mohs; pale lavender to purple, vitreous luster, hexagonal crystal structure, and no true cleavage (conchoidal fracture). The specimen appears to be amethyst crystals on a white quartz or pale mineral matrix.

Identified August 17, 2026More mineral →

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Physical properties

Formation & geological history

Forms when iron-bearing quartz crystals develop purple coloration through natural irradiation, commonly in volcanic cavities and hydrothermal veins. Most specimens formed during relatively young to ancient volcanic episodes; exact age requires locality data.

Uses & applications

Used as a decorative and collectible mineral specimen, and occasionally in jewelry after cutting. Common commercial pieces typically have modest value.

Geological facts

Purple color intensity depends on iron content and irradiation; heating can turn some amethyst yellow-orange, producing citrine. Amethyst is February’s birthstone.

Field identification & locations

Identify by hard, glassy hexagonal crystals, purple zoning, and ability to scratch glass; unlike fluorite, it lacks cleavage and is harder. Major sources include Brazil, Uruguay, Zambia, and Mexico.