mineral

Raw amethyst (purple quartz)

Amethyst; quartz, SiO₂, colored by trace iron and irradiation

AI-generated identification · may be incorrect

Hardness 7 Mohs; pale lavender-purple color, vitreous luster, translucent appearance, and conchoidal fracture. Hexagonal quartz structure; no cleavage; typical specific gravity ~2.65.

Identified August 11, 2026More mineral →

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Physical properties

Hardness 7 Mohs; pale lavender-purple color, vitreous luster, translucent appearance, and conchoidal fracture. Hexagonal quartz structure; no cleavage; typical specific gravity ~2.65.

Formation & geological history

Forms when silica-rich hydrothermal fluids or volcanic gas cavities deposit quartz, with iron impurities producing purple color. Commonly associated with relatively young to ancient volcanic rocks, especially basalt geodes.

Uses & applications

Used as a gemstone, ornamental stone, crystal specimen, and in carvings; crushed quartz also has industrial applications. This small rough piece has modest commercial value.

Geological facts

Amethyst is the purple variety of quartz and can fade with prolonged heat or strong sunlight. Its color commonly varies from very pale lilac to deep violet.

Field identification & locations

Identify by its purple color, glassy luster, hardness, and lack of cleavage; it should scratch glass but not be scratched by a steel knife. Major sources include Brazil, Uruguay, Zambia, and Namibia.