mineral

Amethyst crystal cluster

Amethyst, purple variety of quartz (SiO₂)

AI-generated identification · may be incorrect

Pale lavender to purple, vitreous luster, with clusters of pointed quartz crystals; Mohs hardness 7 and no cleavage. The tan crystal attached at the front appears to be a different mineral, but cannot be identified confidently from the photo.

Identified October 9, 2026More mineral →

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Physical properties

Formation & geological history

Quartz crystals grew in a cavity in volcanic rock from silica-bearing fluids; purple color comes chiefly from trace iron and natural radiation. The specimen’s geological age and exact locality cannot be determined from the image.

Uses & applications

Used for mineral collecting, décor, and jewelry; amethyst is commonly cut into gems, though this cluster is better suited to display.

Geological facts

Amethyst is quartz with the same chemical composition as colorless rock crystal; its color may fade with prolonged strong sunlight.

Field identification & locations

Identify by purple color, glassy pointed crystals, and hardness that can scratch glass. Amethyst occurs worldwide, notably in Brazil, Uruguay, and Zambia; the attached tan crystal may help identify the locality if examined in person.