mineral

Amethyst-bearing quartz

Quartz, SiO₂; purple color from trace iron and irradiation

AI-generated identification · may be incorrect

Hardness 7 Mohs; translucent white to lilac-purple; vitreous to somewhat dull luster; trigonal crystal structure, usually massive here, with no true cleavage and conchoidal fracture. The pale cream material may be quartz, feldspar, or iron-stained matrix.

Identified September 14, 2026More mineral →

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Physical properties

Formation & geological history

Forms when silica-rich hydrothermal fluids fill cavities and fractures, where quartz crystals grow over time; commonly associated with volcanic rocks, typically Cenozoic to older deposits. The specimen appears rough and natural rather than cut or tumbled.

Uses & applications

Used for jewelry, carvings, ornaments, mineral collecting, and metaphysical items; massive low-grade material has limited industrial value compared with clear quartz.

Geological facts

Amethyst is purple quartz, with color intensity varying according to iron content and irradiation. Heating can turn some amethyst yellow-orange, producing citrine-like material.

Field identification & locations

Identify by its purple quartz color, glassy fracture, hardness, and inability to scratch with a steel knife; it should scratch ordinary glass. Common localities include Brazil, Uruguay, Zambia, and Mexico.