Rock Identifier
Amethyst quartz cluster (Quartz, SiO₂; purple variety amethyst) — mineral
mineral

Amethyst quartz cluster

Quartz, SiO₂; purple variety amethyst

AI-generated identification · may be incorrect

Mohs hardness 7; vitreous luster; transparent to translucent; conchoidal fracture and no cleavage; trigonal crystal structure. Purple color comes from irradiation and trace iron, with white quartz and possible iron staining visible.

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Physical properties

Mohs hardness 7; vitreous luster; transparent to translucent; conchoidal fracture and no cleavage; trigonal crystal structure. Purple color comes from irradiation and trace iron, with white quartz and possible iron staining visible.

Formation & geological history

Forms when silica-rich hydrothermal fluids fill cavities in volcanic rocks, especially basaltic geodes. Most specimens formed in relatively young volcanic settings, commonly during the Cenozoic, though exact age depends on locality.

Uses & applications

Used as a decorative and collectible mineral, in jewelry, carvings, and limited industrial quartz applications. This hand-sized cluster is primarily a display specimen.

Geological facts

The specimen appears to be a natural amethyst cluster with pale lilac, hexagonal crystal points rather than a polished or synthetic piece.

Field identification & locations

Identify by purple color, six-sided quartz crystals, glassy luster, and hardness sufficient to scratch ordinary glass; it should not react with dilute acid. Common sources include Brazil, Uruguay, Zambia, and Mexico.