Rock Identifier
Amethyst crystal (Quartz (SiO₂), purple variety colored by trace iron and irradiation) — mineral
mineral

Amethyst crystal

Quartz (SiO₂), purple variety colored by trace iron and irradiation

AI-generated identification · may be incorrect

Mohs hardness 7; translucent purple with vitreous luster and hexagonal crystal form. The pointed termination and visible faces are consistent with a small quartz crystal.

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Physical properties

Mohs hardness 7; translucent purple with vitreous luster and hexagonal crystal form. The pointed termination and visible faces are consistent with a small quartz crystal.

Formation & geological history

Amethyst forms as quartz crystals in mineral-rich fluids within cavities, commonly in volcanic rocks; its age varies with the deposit. The image does not establish its geological source or age.

Uses & applications

Used in jewelry, ornaments, and mineral collections; small crystals are widely sold as specimens.

Geological facts

Amethyst’s purple color is associated with trace iron and natural radiation exposure; heating can turn some amethyst yellow or orange, resembling citrine.

Field identification & locations

Common sources include Brazil, Uruguay, and Zambia. Identify it by its purple color, glassy luster, pointed quartz termination, and hardness sufficient to scratch glass.