mineral

Amethyst quartz fragment

Quartz, SiO₂; purple coloration from iron-related defects and irradiation

AI-generated identification · may be incorrect

Mohs hardness 7; translucent pale purple with vitreous luster and conchoidal fracture. Trigonal crystal structure; no true cleavage; specific gravity about 2.65.

Identified August 15, 2026More mineral →

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Physical properties

Mohs hardness 7; translucent pale purple with vitreous luster and conchoidal fracture. Trigonal crystal structure; no true cleavage; specific gravity about 2.65.

Formation & geological history

Forms when silica-rich hydrothermal fluids fill cavities in volcanic rocks, commonly alongside white or colorless quartz. Most deposits formed in geologically young-to-ancient basaltic geodes; the photograph alone cannot determine age or locality.

Uses & applications

Used as a gemstone, mineral specimen, ornamental stone, and in metaphysical collecting. Small rough fragments commonly have little commercial value.

Geological facts

Amethyst is the purple variety of quartz; heating can turn it yellow-orange, producing citrine. Color intensity varies with iron content and irradiation.

Field identification & locations

Identify by its purple color, glassy luster, hardness, and lack of cleavage; it can scratch ordinary glass but should be confirmed by testing, as pale fluorite or glass may look similar. Common sources include Brazil, Uruguay, Zambia, and Bolivia.