mineral

Amethyst in quartz

Amethyst, purple quartz (SiO₂), with colorless/milky quartz

AI-generated identification · may be incorrect

Mohs hardness 7; purple and white, vitreous luster, trigonal crystal structure, no true cleavage, conchoidal fracture; specific gravity about 2.65.

Identified October 3, 2026More mineral →

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Physical properties

Mohs hardness 7; purple and white, vitreous luster, trigonal crystal structure, no true cleavage, conchoidal fracture; specific gravity about 2.65.

Formation & geological history

Quartz crystallizes from silica-rich fluids in cavities and veins; trace iron and natural irradiation produce amethyst’s purple color. The specimen’s exact age and locality cannot be determined from the image.

Uses & applications

Used for jewelry, ornaments, and mineral collecting; quartz is also important in electronics and industry.

Geological facts

Amethyst is the purple variety of quartz, and its color may fade with prolonged strong sunlight or heating.

Field identification & locations

The visible purple-and-white quartz is consistent with rough amethyst, but confirm by hardness and other tests; common sources include Brazil, Uruguay, and Zambia.