mineral

Amethyst crystal cluster

Amethyst, purple variety of quartz (SiO₂)

AI-generated identification · may be incorrect

Mohs hardness 7; purple, vitreous luster, hexagonal crystal system, and no cleavage. The specimen shows clustered, pointed quartz crystals.

Identified September 28, 2026More mineral →

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Physical properties

Mohs hardness 7; purple, vitreous luster, hexagonal crystal system, and no cleavage. The specimen shows clustered, pointed quartz crystals.

Formation & geological history

Forms when silica-rich fluids deposit quartz in cavities, commonly in volcanic rocks; its purple color comes from trace iron and natural irradiation. The image does not establish the specimen’s age or locality.

Uses & applications

Used in jewelry, ornamentation, and mineral collecting; lower-grade material is also used for carvings and decorative objects.

Geological facts

Amethyst is quartz colored by iron-related defects in its crystal structure; heating can produce yellow or orange citrine-like colors.

Field identification & locations

Identify by its purple color, glassy luster, and hardness; major sources include Brazil, Uruguay, Zambia, and Madagascar. Avoid cleaning with harsh chemicals or prolonged strong sunlight.