mineral

Amethyst (likely)

Quartz, SiO₂; purple variety called amethyst

AI-generated identification · may be incorrect

Small rough purple translucent crystal with vitreous luster and probable quartz fracture; Mohs hardness 7, no cleavage, hexagonal crystal system, specific gravity about 2.65. Color is caused mainly by iron impurities and irradiation.

Identified August 23, 2026More mineral →

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Physical properties

Formation & geological history

Forms when silica-rich hydrothermal fluids or groundwater fill cavities in volcanic rocks, commonly alongside clear or white quartz. Most amethyst formed in volcanic cavities during relatively young Phanerozoic geological episodes, though exact age requires locality data.

Uses & applications

Used as a gemstone, mineral specimen, ornamental stone, and source material for carved objects; usually modestly priced unless strongly colored and well crystallized.

Geological facts

The visible purple color can fade with prolonged heating or intense sunlight. Natural amethyst commonly occurs as crystal-lined geodes and druzy coatings.

Field identification & locations

Identify with hardness testing against glass, vitreous luster, conchoidal fracture, and purple zoning; confirm with locality, crystal form, or gemological testing because dyed glass and purple fluorite can look similar. Common sources include Brazil, Uruguay, Zambia, and Siberia.